JAVA2EVERYONE

Create Java MP3 To Wav Converter

2011-01-30T06:52:00.001+08:00

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COMPLETE SOURCE CODE FOR : MainClass.java
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COMPLETE SOURCE CODE FOR : SwingWorker.java
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Select all JCheckBox in one click

2010-12-23T16:08:00.000+08:00

Watch video below :

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COMPLETE SOURCE CODE FOR : JCheckBoxMultipleSelectInOneClick.java
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import javax.swing.JCheckBox;
import javax.swing.JFrame;

import java.awt.GridLayout;

import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;

public class JCheckBoxMultipleSelectInOneClick extends JFrame implements ActionListener
{
 //Create JCheckBox object
 JCheckBox a=new JCheckBox("Select All");
 JCheckBox b=new JCheckBox("Car");
 JCheckBox c=new JCheckBox("Lorry");
 JCheckBox d=new JCheckBox("Motorcycle");
 
 //Constructor for JCheckBoxMultipleSelectInOneClick class
 public JCheckBoxMultipleSelectInOneClick()
 {
  //Set JFrame title
  super("Select All JCheckBox In One Click");
  
  //Set JFrame layout
  setLayout(new GridLayout(4,1));
  
  //Add action listener to JCheckBox a
  a.addActionListener(this);
  
  //Add JCheckBox into JFrame
  add(a);
  add(b);
  add(c);
  add(d);
  
  //Set JFrame's default close operation when click on close window button
  setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
  
  //Set JFrame size
  setSize(400,400);
  
  //Make JFrame locate at the center of screen
  setLocationRelativeTo(null);
  
  //Make JFrame visible to see
  setVisible(true);
 }
 
 //Override actionPerformed method in ActionListener interface
 public void actionPerformed(ActionEvent e)
 {
  if(e.getSource()==a)
  {
   //Set all JCheckBox to select when JCheckBox a is select  
   if(a.isSelected()==true)
   {
    b.setSelected(true);
    c.setSelected(true);
    d.setSelected(true);
   }
   
   //Set all JCheckBox to unselect when JCheckBox a is select 
   else
   {
    b.setSelected(false);
    c.setSelected(false);
    d.setSelected(false);
   }
  }
 }

 //Main method where this program start
 public static void main(String[]args)
 {
  JCheckBoxMultipleSelectInOneClick myFirstObject = new JCheckBoxMultipleSelectInOneClick();
 }
}

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JUST COMPILE AND EXECUTE IT
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A Java Program To Play A MP3 File Using JLayer

2010-12-21T18:58:00.001+08:00

Watch video tutorial below :

*********************************************************************
COMPLETE SOURCE CODE FOR : TestPlay.java
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import javazoom.jl.player.Player;
import java.io.FileInputStream;

public class TestPlay
{
    public static void main(String[]args)
    {
        try
        {
            FileInputStream fis=new FileInputStream("C:\\Documents and Settings\\UserXP\\Desktop\\01-flo_rida_(feat_david_guetta)-clab_cant_handle_me.mp3");
            Player playMp3=new Player(fis);

            playMp3.play();
        }
        catch(Exception e)
        {
            System.out.println(e);
        }
    }
}

Open folder or directory in Windows 7 using java

2010-09-14T21:59:00.000+08:00

Complete source code below will show you, how to open folder through java in Windows 7.

************************************************************************
COMPLETE SOURCE CODE FOR : OpenFolderInJava.java
Thank you to Ankur Pandya for this source codes.
************************************************************************

/// file OpenFolderInJava.java ////

import java.util.*;
import java.io.*;
import java.awt.Desktop;

class OpenFolderInJava{

public static void main(String[] arg){
String path = "."; // path to the directory to be opened
File file = new File("C:\\");
Desktop desktop = null;
// Before more Desktop API is used, first check
// whether the API is supported by this particular
// virtual machine (VM) on this particular host.
if (Desktop.isDesktopSupported()) {
desktop = Desktop.getDesktop();
}
try {
desktop.open(file);
}
catch (IOException e){
}
}
}

/// end of file ///

************************************************************************
JUST COMPILE AND EXECUTE
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Java Play Sound When Click On Letter

2010-09-10T11:47:00.001+08:00

Click here to download complete file from file sharing website.

How To Retrieve Data Into Database

2010-04-02T12:07:00.002+08:00

Contributor : Santosh Rai

Program Description : How To Retrieve Data Into Database

Click Here To Download File For This Java Program

Java Address Book

2010-03-31T00:45:00.002+08:00

Contributor : KaliRagavendran

Program Description : Small Address Book

Click Here To Download File For This Java Program

Java Hotel Management Program (Philippine)

2010-03-28T01:18:00.003+08:00

*********************************************************************
COMPLETE SOURCE CODE FOR : TTKH.java
BY : Phi
*********************************************************************


/**
 * @(#)TTKH.java
 *
 * TTKH application
 *
 * @author 
 * @version 1.00 2010/3/21
 */
import javax.swing.*;
import java.awt.*;

public class TTKH {
     
    public static void main(String[] args) {
     try {
     // Set System L&F
        UIManager.setLookAndFeel(
            UIManager.getSystemLookAndFeelClassName());
    } 
    catch (UnsupportedLookAndFeelException e) {
       // handle exception
    }
    catch (ClassNotFoundException e) {
       // handle exception
    }
    catch (InstantiationException e) {
       // handle exception
    }
    catch (IllegalAccessException e) {
       // handle exception
    }
    
    
    //=----------------------------------------------------
     
     // TODO, add your application code
     JFrame frame = new JFrame();
     
     
     JPanel panel = new JPanel();
     JPanel khungchitiet = new JPanel();
     //JPanel p1 = new JPanel();
     
     //JPanel p2 = new JPanel();
     //p2.setLayout(new FlowLayout());
     JPanel khungtimkiem = new JPanel();
     GridLayout g2 = new GridLayout(2,2);
     khungtimkiem.setLayout(new GridLayout(5,2,10,10));
     GridLayout g1 = new GridLayout(1,1);
     khungchitiet.setLayout(new GridLayout(7,2,10,10));
     frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
     
    // frame.setLocationByPlatform(true);
     
     frame.setSize(680,470); 
     
      
     // Giao dien
      
     JLabel ldemuc = new JLabel("Thong Tin Khach Hang"); 
     ldemuc.setFont(new Font("Tahoma", Font.BOLD, 25));
     ldemuc.setLayout(new FlowLayout());
     panel.add(ldemuc);
     
      
     
     // Khung Chi tiet
     JLabel ltenKH = new JLabel("Ten KH");
     JTextField ttenKH = new JTextField("Nguyen Van A",1);
     JLabel lngaynhan = new JLabel("Ngay Nhan Phong");
     JTextField tngaynhan = new JTextField("12/05/2009",1);
     JLabel lngaysinh = new JLabel("Ngay Sinh");
     JTextField tngaysinh = new JTextField("11/09/1986",1);
     JLabel lngaytra = new JLabel("Ngay Tra Phong") ;
     JTextField tngaytra = new JTextField("22/05/2009",1);
     JLabel lgioitinh = new JLabel("Gioi Tinh");
     JTextField tgioitinh = new JTextField("Nam",1);
     JLabel lsodt = new JLabel("So Dien Thoai");
     JTextField tsodt = new JTextField("0912345677",1);
     JLabel lloaiphong = new JLabel("Loai Phong");
     JTextField tloaiphong = new JTextField("Vip",1);
     JLabel lcmnd = new JLabel("So CMND");
     JTextField tcmnd = new JTextField("036365888",1);
     JLabel lmaKH = new JLabel("Ma KH");
     JTextField tmaKH = new JTextField("001",1);
     JLabel lemail = new JLabel("Email");
     JTextField temail = new JTextField("nguoidep@gmail.com",1);
     JLabel lspace = new JLabel("--------------");
     JLabel lspace1 = new JLabel(" ");
     JLabel lspace2 = new JLabel("");
     JLabel lspace3 = new JLabel("--------------");
     JLabel lspace4 = new JLabel(" ");
     JLabel lspace5 = new JLabel(" ");
     JLabel lchitiet = new JLabel("Chi Tiet Khach Hang") ;
     lchitiet.setFont(new Font("Tahoma", Font.BOLD, 15));
     JLabel ltimkiem = new JLabel("Tim Kiem Nhanh") ;
     ltimkiem.setFont(new Font("Tahoma", Font.BOLD, 15));
     
        
      
     khungchitiet.add(lchitiet);  
     khungchitiet.add(lspace);
     khungchitiet.add(lspace1); 
     khungchitiet.add(lspace2);
     //khungchitiet.add(lspace3); 
     khungchitiet.add(lmaKH);
     khungchitiet.add(tmaKH);
     khungchitiet.add(lngaynhan);
     khungchitiet.add(tngaynhan);
     khungchitiet.add(ltenKH);
     khungchitiet.add(ttenKH);
     khungchitiet.add(lngaytra);
     khungchitiet.add(tngaytra);
     khungchitiet.add(lgioitinh);
     khungchitiet.add(tgioitinh);
     khungchitiet.add(lsodt);
     khungchitiet.add(tsodt);
     khungchitiet.add(lngaysinh);
     khungchitiet.add(tngaysinh);
     khungchitiet.add(lloaiphong);
     khungchitiet.add(tloaiphong);
     khungchitiet.add(lcmnd);
     khungchitiet.add(tcmnd);
     khungchitiet.add(lemail);
     khungchitiet.add(temail); 
     khungchitiet.add(ltimkiem);
     khungchitiet.add(lspace3);
     khungchitiet.add(lspace4);
     khungchitiet.add(lspace5); 
            
          
     
                  
     // phan tim kiem  
     
     JLabel lmaKH2 = new JLabel("Ma KH");
     lmaKH2.setForeground(Color.red);
     JTextField tmaKH2 = new JTextField("Nhap ma khach hang...");
     Choice c1 = new Choice();
     c1.addItem("Vip");
     c1.addItem("Phong Gia dinh"); 
     c1.addItem("Phong Quat");
     c1.addItem("Phong May lanh");
     //JLabel lgioitinh2 = new JLabel("Gioi tinh");
     //JRadioButton rnam = new JRadioButton("Nam",true);
     //JRadioButton rnu = new JRadioButton("Nu",false); 
     JLabel lngaynhan2 = new JLabel("Ngay Nhan");
     lngaynhan2.setForeground(Color.red);
     JTextField tngaynhan2 = new JTextField("Nhap ngay nhan dd/mm/yyyy");
     JLabel lcmnd2 = new JLabel("So CMND");
     JTextField tcmnd2 = new JTextField("Nhap so");
     JLabel lngaytra2 = new JLabel("Ngay Tra");
     lngaytra2.setForeground(Color.red);
     JTextField tngaytra2 = new JTextField("Nhap ngay tra dd/mm/yyyy");
     JLabel ltenKH2 = new JLabel("Ten KH");
     JTextField ttenKH2 = new JTextField("Nhap ten KH");
     JLabel ls1 = new JLabel(" ");
     JLabel ls2 = new JLabel(" ");
     JLabel ls3 = new JLabel(" ");
     JLabel ls4 = new JLabel(" ");
     JLabel ls5 = new JLabel(" ");
     JLabel ls6 = new JLabel(" ");
     JButton b1 = new JButton("Lam Moi");
      JButton b2 = new JButton("Tim");
     JButton b3 = new JButton("Thoat");
     //JLabel ls5 = new JLabel(" ");
     JLabel loaiphong = new JLabel("Loai Phong");
     khungtimkiem.add(lmaKH2);
     khungtimkiem.add(tmaKH2);
     khungtimkiem.add(lngaynhan2);
     khungtimkiem.add(tngaynhan2);
     khungtimkiem.add(ltenKH2);
     khungtimkiem.add(ttenKH2);
     khungtimkiem.add(lngaytra2);
     khungtimkiem.add(tngaytra2);
     khungtimkiem.add(lcmnd2);
     khungtimkiem.add(tcmnd2);
     khungtimkiem.add(ls1);
     khungtimkiem.add(ls2);
     khungtimkiem.add(loaiphong);
     khungtimkiem.add(c1);
     khungtimkiem.add(ls3);
     khungtimkiem.add(b2);
     khungtimkiem.add(ls5);
     khungtimkiem.add(ls6);
     khungtimkiem.add(b1);
     khungtimkiem.add(b3);
     
          
     frame.setLayout(new BorderLayout());
     frame.add(panel, BorderLayout.NORTH);
     //frame.add(p1, BorderLayout.LINE_START);
     frame.add(khungchitiet, BorderLayout.WEST);
     //frame.add(p2, BorderLayout.WEST);
     //frame.add(p2, BorderLayout.LINE_END);
     frame.add(khungtimkiem, BorderLayout.SOUTH);
     frame.setVisible(true);
    }
}

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JUST COMPILE AND EXECUTE IT
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Java radians to degree

2009-07-16T23:18:00.005+08:00

::Click Here To Download File For This Tutorial::

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COMPLETE SOURCE CODE FOR : RadiansToDegree.java
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public class RadiansToDegree
{
public static void main(String[]args)
{
//radians value
double radians=1.5707963267948966;

//Get degree value for radians value equal to 1.5707963267948966
double degree=Math.toDegrees(radians);

System.out.println(degree);
}
}

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JUST COMPILE AND EXECUTE IT
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Java degree to radians

2009-07-16T23:01:00.006+08:00

::Click Here To Download File For This Tutorial::

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COMPLETE SOURCE CODE FOR : DegreeToRadians.java
*********************************************************************


public class DegreeToRadians
{
public static void main(String[]args)
{
//90 degree
double degree=90;

//Get radians value for 90 degree
double radians=Math.toRadians(degree);

System.out.println(radians);
}
}

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JUST COMPILE AND EXECUTE IT
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EzIcon

2009-06-22T22:26:00.003+08:00

::Click Here To Download EzIcon::

You can use this small tool to convert windows icon file (.ico) to 5 other images format like below

.tga
.bmp
.jpeg
.png
.psd

JAutorunKiller

2009-06-22T22:09:00.003+08:00

You can use this small tool to remove autorun file(autorun.inf) that usually use by computer viruses to start their program from removable drive. This is not mean autorun file is a malicious file. Autorun file is always use in compact disc when disc creator want executable file in the compact disc execute when user click on cd drive icon.Click link below to download :
JAutorunKiller.jar

Free java decompiler

2009-04-28T21:59:00.006+08:00

This is one of java decompiler that can be use to get java source file (file with .java as it's file extension) from any java class file (file with .class as it's file extension). Class file is a result after compiling process success without any syntax error.

Click link below to download

1. JD-GUI

2. Cavaj Java Decompiler

3. JCavaj Java Decompiler

Java get binary value from alphabet

2009-04-22T01:08:00.004+08:00

Today, i have learned about how to get binary value from alphabet. You can try compile and execute java program below to get all binary value for A-Z and a-z.

::Click Here To Download File For This Tutorial::

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COMPLETE SOURCE CODE FOR : JavaGetBinaryFromLetter.java
*********************************************************************


public class JavaGetBinaryFromLetter
{
public static void main(String[]args)
{
 String a="ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";

 for(int i=0;i<a.length();i++)
 {
  char b=a.charAt(i);
  int temp=(int)b;
  String c=Integer.toBinaryString(temp);
  System.out.println("BINARY VALUE FOR LETTER "+b+" IS : "+c);
 }
}
}

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JUST COMPILE AND EXECUTE IT
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Java ternary operator

2009-04-18T01:58:00.004+08:00

Today i have learned about ternary operator in java. Before this, when i found it in java code, i will ask myself what it is and what we call it...now i will share with you what i understand about ternary operator.Now, see java code below

::Click Here To Download This Java Source Code::

************************************************************
COMPLETE SOURCE CODE FOR : JavaTernaryOperator.java
************************************************************


public class JavaTernaryOperator
{
public static void main(String[]args)
{
int a=0;
int b=4;
int c=5;

//THIS IS EXAMPLE OF TERNARY OPERATOR
a=(b>c?b:c);

System.out.println(a);
}
}

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In the java code above, example of ternary operator is a=(b>c?b:c);.So, what it mean ?

This is the answer :
Value a is equal to b if b larger than c or value a is equal to c if b smaller than c.So, java code above has same meaning with java code below.

::Click Here To Download This Java Source Code::


public class JavaTernaryOperator
{
public static void main(String[]args)
{
int a=0;
int b=4;
int c=5;

if(b>c)
{
 a=b;
}
else
{
 a=c;
}

System.out.println(a);
}
}

Now, you can choose which one you want to use when write your java program. It seem when we use ternary operator we can make our program more shorter.

Java hexadecimal to binary

2009-04-15T01:17:00.004+08:00

Complete source code below is a simple java program that can be use to get binary value from hexadecimal value.

******************************************************************
COMPLETE SOURCE CODE FOR : JavaHexToBin.java
******************************************************************

::Click Here To Download This Java Source Code::


import java.util.Scanner;

public class JavaHexToBin
{
public static void main(String[]args)
{
 String[]hex={"0","1","2","3","4","5","6","7","8","9","A","B","C","D","E","F"};
 String[]binary={"0000","0001","0010","0011","0100","0101","0110","0111","1000","1001","1010","1011","1100","1101","1110","1111"};

 Scanner s=new Scanner(System.in);
 System.out.print("Put hex value : ");
 String userInput=s.next();
 String result="";
 for(int i=0;i<userInput.length();i++)
 {
  char temp=userInput.charAt(i);
  String temp2=""+temp+"";
  for(int j=0;j<hex.length;j++)
  {
   if(temp2.equalsIgnoreCase(hex[j]))
   {
    result=result+binary[j];
   }
  }
 }
 System.out.println("IT'S BINARY IS : "+result);
}
}

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JUST COMPILE AND EXECUTE IT
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Java determine pixel was clicked or not

2009-04-14T21:19:00.005+08:00

Complete source code below just a simple java program that will determine if you was clicked or not on 8 black dots. If you was clicked , program will inform you that the dot was clicked.I hope you can see all 8 black dots that i mean because it is too small and try click on it to see what happen.

***************************************************************************
COMPLETE SOURCE CODE FOR : JavaDeterminePixelClicked.java
***************************************************************************

::Click Here To Download This Java Source Code::


import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

public class JavaDeterminePixelClicked extends Canvas implements MouseListener
{
 boolean [] con={ false,false,false,false,false,false,false,false };
 int[][]coor=new int[8][2];
 Robot r;
 
 public JavaDeterminePixelClicked()
 {
  addMouseListener(this);
  try
  {
   r=new Robot();
  }
  catch(Exception exception)
  {
   exception.printStackTrace();
  }

  JFrame a=new JFrame(">>>>>TRY CLICK AT BLACK DOT<<<<<");
  a.getContentPane().add(this,BorderLayout.CENTER);
  a.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
  a.setSize(500,500);
  a.setLocationRelativeTo(null);
  a.setVisible(true);
 }
 
 public void paint(Graphics g)
 {
  setBackground( new Color (255,255,255) );
  super.paint(g);
  g.setColor( new Color (0,0,0) );
  g.drawLine(30,30,30,30);
  g.drawLine(40,40,40,40);
  g.drawLine(50,50,50,50);
  g.drawLine(60,60,60,60);
  g.drawLine(70,70,70,70);
  g.drawLine(80,80,80,80);
  g.drawLine(90,90,90,90);
  g.drawLine(100,100,100,100);
 }
 
 public void mouseClicked(MouseEvent event)
 {
  Color temp=r.getPixelColor(event.getLocationOnScreen().x,event.getLocationOnScreen().y);
  if(temp.getRed()==0&&temp.getGreen()==0&&temp.getBlue()==0)
  {
   int upperLeftX=getLocationOnScreen().x;
   int upperLeftY=getLocationOnScreen().y;
   int currentX=event.getLocationOnScreen().x;
   int currentY=event.getLocationOnScreen().y;
   if(currentX-upperLeftX==30&¤tY-upperLeftY==30)
   {
    if(con[0]==false)
    {
     con[0]=true;
    }
    else
    {
     JOptionPane.showMessageDialog(null,"This point was clicked");
    }
   }
   if(currentX-upperLeftX==40&¤tY-upperLeftY==40)
   {
    if(con[1]==false)
    {
     con[1]=true;
    }
    else
    {
     JOptionPane.showMessageDialog(null,"This point was clicked");
    }
   }
   if(currentX-upperLeftX==50&¤tY-upperLeftY==50)
   {
    if(con[2]==false)
    {
     con[2]=true;
    }
    else
    {
     JOptionPane.showMessageDialog(null,"This point was clicked");
    }
   }
   if(currentX-upperLeftX==60&¤tY-upperLeftY==60)
   {
    if(con[3]==false)
    {
     con[3]=true;
    }
    else
    {
     JOptionPane.showMessageDialog(null,"This point was clicked");
    }
   }
   if(currentX-upperLeftX==70&¤tY-upperLeftY==70)
   {
    if(con[4]==false)
    {
     con[4]=true;
    }
    else
    {
     JOptionPane.showMessageDialog(null,"This point was clicked");
    }
   }
   if(currentX-upperLeftX==80&¤tY-upperLeftY==80)
   {
    if(con[5]==false)
    {
     con[5]=true;
    }
    else
    {
     JOptionPane.showMessageDialog(null,"This point was clicked");
    }
   }
   if(currentX-upperLeftX==90&¤tY-upperLeftY==90)
   {
    if(con[6]==false)
    {
     con[6]=true;
    }
    else
    {
     JOptionPane.showMessageDialog(null,"This point was clicked");
    }
   }
   if(currentX-upperLeftX==100&¤tY-upperLeftY==100)
   {
    if(con[7]==false)
    {
     con[7]=true;
    }
    else
    {
     JOptionPane.showMessageDialog(null,"This point was clicked");
    }
   }
  }
 }
 
 public void mouseEntered(MouseEvent event)
 {
  //NOTHING
 }
 
 public void mouseExited(MouseEvent event)
 {
  //NOTHING
 }
 
 public void mousePressed(MouseEvent event)
 {
  //NOTHING
 }
 
 public void mouseReleased(MouseEvent event)
 {
  //NOTHING
 }
 
 public static void main(String[]args)
 {
  JavaDeterminePixelClicked jdpc = new JavaDeterminePixelClicked ();
 }
}

***************************************************************************
JUST COMPILE AND EXECUTE IT
***************************************************************************

Java get degree from radian

2009-04-13T23:03:00.003+08:00

Complete source code below just a simple java program that we can use to get degree value from radian value.

*****************************************************************
COMPLETE SOURCE CODE FOR : GetDegreeFromRadian.java
*****************************************************************

::Click Here To Download This Java Source Code::


public class GetDegreeFromRadian
{
public static void main(String[]args)
{
 //CHANGE RADIAN VALUE TO WHAT VALUE THAT YOU WANT
 double radian=1.00;

 //PRINT ANGLE VALUE THAT WE GET FROM RADIAN
 System.out.println( "IT'S ANGLE IS : " + radian* (180/Math.PI) );
}
}

*****************************************************************
JUST COMPILE AND EXECUTE IT
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Java receive user input and sort it in ascending order

2009-04-11T21:21:00.004+08:00

Complete source code below is a simple java program that will receive user input and after that sort it in ascending order before display it's result.

*********************************************************************
COMPLETE SOURCE CODE FOR : AscendingString.java
*********************************************************************

::Click Here To Download This Java Source Code::


import java.util.Scanner;

public class AscendingString
{
public static void main(String[]args)
{
 Scanner s=new Scanner(System.in);
 String[]a=new String[5];
 for(int i=0;i<5;i++)
 {
  System.out.println(i+1+".Put your String");
  String temp=s.nextLine();
  a[i]=temp;
 }

 System.out.println("**********");
 System.out.println("RESULT");
 System.out.println("**********");

 for(int i=0;i<5;i++)
 {
  for(int j=0;j<5;j++)
  {
   String temp=a[i];
   String tempB=a[j];
   if(temp.compareTo(tempB)<0)
   {
    a[i]=tempB;
    a[j]=temp;
   }
  }
 }

 for(int i=0;i<5;i++)
 {
  System.out.println(a[i]);
 }
}
}

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Java recursive method

2009-04-11T14:44:00.007+08:00

Sometime we need to solve a problem using the same way. For example you need to build a program that will print number from 1 until number that input by a user. First program will print number without using recursive technique and second program we will use recursive technique to print number from 1 until number that input by a user.You should see how a recursive method will do the same thing until problem solve.

FIRST PROGRAM :

::Click Here To Download This Java Source Code::


import java.util.Scanner;

public class Test
{
public static void main(String[]args)
{
Scanner s=new Scanner(System.in);
System.out.println("Put a number");
int a=s.nextInt();

System.out.println("IT'S RESULT");
System.out.println("***************");

for(int i=1;i<=a;i++)
{
System.out.println(i);
}
}
}

SECOND PROGRAM :
print method in PrintNumber class is example of recursive method.

::Click Here To Download This Java Source Code::


import java.util.Scanner;

public class Test
{
public static void main(String[]args)
{
Scanner s=new Scanner(System.in);
System.out.println("Put a number");
int myNumber=s.nextInt();
PrintNumber pn=new PrintNumber();
System.out.println("IT'S RESULT");
System.out.println("***************");
pn.print(myNumber);
}
}

class PrintNumber
{
public void print(int a)
{
if(a==1)
{
System.out.println(a);
}
else
{
int temp=a-1;
print(temp);
System.out.println(a);
}
}
}

For example if you put 2 into second program, when it enter print method in PrintNumber class, firstly program will check if the number is 1 or not. If not, the number will be minus with 1 before it send it's result to print method again. In this case it will send 1 to print method. So System.out.println(a) for a=2 will stop for a while until a=1. Now after it send 1 to print method, condition for a==1 will be true. 1 will be print, and System.out.println(a) for a=2 will continue again by print 2.

I hope it will help.

Set JOptionPane background color

2009-04-09T01:32:00.005+08:00

After i make some review over internet and java forum lastly i understand how to change JOptionPane background color.You can try compile and execute simple code below and see it's result.

***************************************************************
COMPLETE SOURCE CODE FOR : SetJOptionPaneBackgroundColor.java
***************************************************************

::Click Here To Download This Java Source Code::


import javax.swing.JOptionPane;
import javax.swing.UIManager;

import javax.swing.plaf.ColorUIResource;

public class SetJOptionPaneBackgroundColor
{
public static void main(String[]args)
{
UIManager uim=new UIManager();
uim.put("OptionPane.background",new ColorUIResource(255,0,0));
uim.put("Panel.background",new ColorUIResource(255,0,0));

JOptionPane.showMessageDialog(null,"Hello world","HELLO WORLD",JOptionPane.INFORMATION_MESSAGE);
}
}

***************************************************************
JUST COMPILE AND EXECUTE IT
***************************************************************

Java count all white space in String

2009-04-06T08:27:00.004+08:00

Yesterday, before i go to sleep i tried to answer a simple question from a site. The question is about how to count all white space from String that input by a user. After a few time i failed, i found code below :

*********************************************************
COMPLETE SOURCE CODE FOR : CountAllWhitespaceInString.java
*********************************************************

::Click Here To Download This Java Source Code::


import java.util.Scanner;

public class CountAllWhitespaceInString
{
public static void main(String[]args)
{
 boolean a=true;
 Scanner sc=new Scanner(System.in);

 while(a)
 {
  System.out.println("Type EXIT to exit");
  String b=sc.nextLine();
  int whitespaceNumber=0;
 
  if(!b.equalsIgnoreCase("exit"))
  {
   try
   {
    for(int i=0;i<=b.length()-1;i++)
    {
     char temp=b.charAt(i);
     if(temp==' ')
     {
      whitespaceNumber++;
     }
    }
    System.out.println("Whitespace number is : "+whitespaceNumber);
   }
   catch(Exception exception)
   {
    System.out.println("DON'T DO THAT");
   }
  }
  else
  {
   a=false;
  }
 }
}
}

*********************************************************
JUST COMPILE AND EXECUTE IT
*********************************************************

Java reverse String and simplest palindrome checker

2009-04-05T22:48:00.005+08:00

Today, i have learn something new and it's totally simple. Sometime when don't know about that, we will use our way that take a time to complete a simple task. What i learn today is, how to reverse String. The easiest way to reverse a String for example from "i love you" to "uoy evol i" is using method reverse() in StringBuffer class. It is also very useful especially when you want to create a palindrome checker program. Your program will be the shortest palindrome checker program in the world i think, hehehehe. I have also created a new one before, but it quit long. You can review it by click here. Now we will go to coding part. I will create two simple programs. Firstly to reverse "i love you" to "uoy evol i". Secondly i will create my shortest palindrome checker program that i ever made. Don't waste our time by hear what i said.

*************************************************************
COMPLETE SOURCE CODE FOR : ReverseString.java
*************************************************************

::Click Here To Download This Java Source Code::


public class ReverseString
{
public static void main(String[]args)
{
String a="i love you";
StringBuffer b=new StringBuffer(a);

System.out.println(b.reverse());
}
}

*************************************************************
LIKE USUAL, JUST COMPILE AND EXECUTE IT
*************************************************************

*************************************************************
COMPLETE SOURCE CODE FOR : MySimplestPalindromeChecker.java
*************************************************************

::Click Here To Download This Java Source Code::


import javax.swing.JOptionPane;

public class MySimplestPalindromeChecker
{
public static void main(String[]args)
{
String a=JOptionPane.showInputDialog(null,"What word that you want to check ?","Palindrome Checker",JOptionPane.QUESTION_MESSAGE);

if(a!=null)
{
String b=a;
StringBuffer c=new StringBuffer(b);
if(a.equals(c.reverse().toString()))
{
 JOptionPane.showMessageDialog(null,"THIS IS A PALINDROME WORD");
}
else
{
 JOptionPane.showMessageDialog(null,"THIS IS NOT A PALINDROME WORD");
}
}
}
}

*************************************************************
JUST COMPILE AND EXECUTE IT
*************************************************************

Square root symbol in java

2009-04-05T03:18:00.004+08:00

After i spend a day to find how to print square root symbol in java through command prompt, someone tell me from java forum if our command prompt did not have a glyph for the square root character, this job will undone. But when i try use it in JOptionPane's message box it perform well.

In java "\u221A" is refer to square root symbol. It is Unicode.You can try to visit link below for more details :
Click here

If you want to print square root symbol through your command prompt, you can try something like this. I hope your command prompt can support for this thing.


public class Test2
{
 public static void main(String[]args)
 {
  System.out.println("\u221A");
 }
}

If you want to put it in JOptionPane's message box (this is perform well in my computer), you can try this :


import javax.swing.JOptionPane;

public class Test2
{
 public static void main(String[]args)
 {
  JOptionPane.showMessageDialog(null,"\u221A");
 }
}

Java simple rgb to hex converter

2009-03-31T22:30:00.006+08:00

Complete source code below is a small java program that convert rgb value to hex value. Now i will share with you how to get hex value from rgb value. Before i go far, let we see a description about hex value structure.

VALUE THAT YOU GET AFTER DIVIDE OR MULTIPLY	0	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15
HEX VALUE	0	1	2	3	4	5	6	7	8	9	A	B	C	D	E	F

TABLE A

For example :
FFFFFF is a hex value for white and it's rgb value is 255 255 255.First FF is value for red, second FF is value for green and last FF is for blue.So it mean, first 255 in rgb is equal to first FF in hex value.Now i will show you, how to get FF from 255.For this tutorial i show you only for red part. You can try other last two part for green and blue. Now take 255 and devide it with 16. You should get 15.9375. Take value before floating point. In this case we get 15. Look at TABLE A at above. 15 is equal to F. Now you get first F.For second F, take value after floating point and multiply it with 16. In this case you should multiply 0.9375 with 16. It's result is equal to 15 and it also hold F.Now you get hex value for red part.I hope you can understand what i tried to say.

********************************************************************
COMPLETE SOURCE CODE FOR : RGBtoHEX.java
********************************************************************

::Click Here To Download This Java Source Code::


import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;

import java.awt.GridLayout;
import java.awt.Color;

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class RGBtoHEX implements ActionListener
{
JTextField r=new JTextField(10);
JTextField g=new JTextField(10);
JTextField b=new JTextField(10);

JLabel rLabel=new JLabel("R",JLabel.CENTER);
JLabel gLabel=new JLabel("G",JLabel.CENTER);
JLabel bLabel=new JLabel("B",JLabel.CENTER);

JPanel panelTextField=new JPanel();
JPanel panelLabel=new JPanel();

JButton button=new JButton("Calculate Now !");

JTextField result=new JTextField(30);

public RGBtoHEX()
{
button.addActionListener(this);

r.setHorizontalAlignment(JTextField.CENTER);
g.setHorizontalAlignment(JTextField.CENTER);
b.setHorizontalAlignment(JTextField.CENTER);

result.setHorizontalAlignment(JTextField.CENTER);
result.setBackground(new Color(255,255,255));
result.setEditable(false);

panelLabel.setLayout(new GridLayout(1,3));
panelLabel.add(rLabel);
panelLabel.add(gLabel);
panelLabel.add(bLabel);

panelTextField.setLayout(new GridLayout(1,3));
panelTextField.add(r);
panelTextField.add(g);
panelTextField.add(b);

JFrame myMainWindow=new JFrame("RGB to HEX");
myMainWindow.getContentPane().setLayout(new GridLayout(4,1));
myMainWindow.getContentPane().add(panelLabel);
myMainWindow.getContentPane().add(panelTextField);
myMainWindow.getContentPane().add(button);
myMainWindow.getContentPane().add(result);

myMainWindow.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
myMainWindow.setSize(300,130);
myMainWindow.setLocationRelativeTo(null);
myMainWindow.setVisible(true);
}

public void actionPerformed(ActionEvent event)
{
try
{
String hexValue="#";
r.setEditable(false);
g.setEditable(false);
b.setEditable(false);

double red=Double.parseDouble(r.getText());
double green=Double.parseDouble(g.getText());
double blue=Double.parseDouble(b.getText());

for(int i=1;i<=3;i++)
{
double temp=0;

if(i==1)
{
 temp=red;
}
else if(i==2)
{
 temp=green;
}
else if(i==3)
{
 temp=blue;
}

double devideResult=temp/16;

String stringDevideResult=Double.toString(devideResult);

int pointIndexInString=stringDevideResult.indexOf(".");

String firstValue=stringDevideResult.substring(0,pointIndexInString);

double multiplySixteen=(devideResult-(Double.parseDouble(firstValue)))*16;

String stringMultiplySixteen=Double.toString(multiplySixteen);

pointIndexInString=stringMultiplySixteen.indexOf(".");

String secondValue=stringMultiplySixteen.substring(0,pointIndexInString);

if(firstValue.equalsIgnoreCase("10"))
{
 firstValue="A";
}
if(firstValue.equalsIgnoreCase("11"))
{
 firstValue="B";
}
if(firstValue.equalsIgnoreCase("12"))
{
 firstValue="C";
}
if(firstValue.equalsIgnoreCase("13"))
{
 firstValue="D";
}
if(firstValue.equalsIgnoreCase("14"))
{
 firstValue="E";
}
if(firstValue.equalsIgnoreCase("15"))
{
 firstValue="F";
}
if(secondValue.equalsIgnoreCase("10"))
{
 secondValue="A";
}
if(secondValue.equalsIgnoreCase("11"))
{
 secondValue="B";
}
if(secondValue.equalsIgnoreCase("12"))
{
 secondValue="C";
}
if(secondValue.equalsIgnoreCase("13"))
{
 secondValue="D";
}
if(secondValue.equalsIgnoreCase("14"))
{
 secondValue="E";
}
if(secondValue.equalsIgnoreCase("15"))
{
 secondValue="F";
}

hexValue=hexValue+firstValue+secondValue;
}


result.setText(hexValue);
r.setEditable(true);
g.setEditable(true);
b.setEditable(true);
}
catch(Exception exception)
{
JOptionPane.showMessageDialog(null,"Program error and it will terminate","ERROR",JOptionPane.ERROR_MESSAGE);
System.exit(0);
}
}

public static void main(String[]args)
{
RGBtoHEX converter=new RGBtoHEX();
}
}

********************************************************************
JUST COMPILE AND EXECUTE IT
********************************************************************

Java simple image magnifier tooltip

2009-03-31T02:04:00.006+08:00

Sometime when we play with images...i mean here a lot of images, like we let user choose an image from 500 images in a JFrame and all images show at the same time without any scrollbar, it can give user a little problem if the image too small. So, how can user make a good choice. This give me some idea to built my own image tooltip. This is a simple tooltip. It will enlarge image when someone hover mouse cursor on it.Image below is a result from program below.

Before you compile and execute it, you should download all images below. After that place them at same location with this java source file.

Love_Music_by_jovincent.jpg

Leafs_1_by_NerghaL.jpg

Hancock-1611.jpg

matrix.jpg

********************************************************************
COMPLETE SOURCE CODE FOR : ImageToolTip.java
********************************************************************

::Click Here To Download File For This Tutorial::


import javax.swing.JPanel;
import javax.swing.ImageIcon;
import javax.swing.JFrame;

import java.awt.GridLayout;
import java.awt.Graphics;

import java.awt.event.MouseListener;
import java.awt.event.MouseEvent;

public class ImageToolTip
{
public static void main(String[]args)
{
 PanelImage imageA=new PanelImage("matrix.jpg");

 PanelImage imageB=new PanelImage("Hancock-1611.jpg");

 PanelImage imageC=new PanelImage("Leafs_1_by_NerghaL.jpg");

 PanelImage imageD=new PanelImage("Love_Music_by_jovincent.jpg");

 JFrame myMainWindow=new JFrame("Image Tool Tip");
 myMainWindow.setResizable(false);
 myMainWindow.getContentPane().setLayout(new GridLayout(2,2));
 myMainWindow.getContentPane().add(imageA);
 myMainWindow.getContentPane().add(imageB);
 myMainWindow.getContentPane().add(imageC);
 myMainWindow.getContentPane().add(imageD);

 myMainWindow.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 myMainWindow.setSize(100,100);
 myMainWindow.setLocationRelativeTo(null);
 myMainWindow.setVisible(true);
}
}

class PanelImage extends JPanel implements MouseListener
{
ImageIcon temp;
ImageMagnifier im;

public PanelImage(String a)
{
 addMouseListener(this);
 temp=new ImageIcon(a);
}

public void paint(Graphics g)
{
 super.paint(g);
 g.drawImage(temp.getImage(),0,0,getSize().width,getSize().height,this);
}

public void mouseClicked(MouseEvent event)
{
}

public void mouseEntered(MouseEvent event)
{
 im=new ImageMagnifier(temp,getSize().width,getSize().height,event.getXOnScreen(),event.getYOnScreen());
}

public void mouseExited(MouseEvent event)
{
 im.dispose();
}

public void mousePressed(MouseEvent event)
{
}

public void mouseReleased(MouseEvent event)
{
}
}

class ImageMagnifier extends JFrame
{
ImageIcon temp;

public ImageMagnifier(ImageIcon imageFile,int width,int height,int x,int y)
{
 setUndecorated(true);
 temp=imageFile;
 setLocation(x,y);
 setSize(width*9,height*9);
 setVisible(true);
}

public void paint(Graphics g)
{
 super.paint(g);
 g.drawImage(temp.getImage(),0,0,getSize().width,getSize().height,this);
}
}

********************************************************************
JUST COMPILE AND EXECUTE IT
********************************************************************

Java print pi value

2009-03-30T00:38:00.004+08:00

Simple java program below will print pi value in command prompt.

****************************************************************
COMPLETE SOURCE CODE FOR : PrintPiValue.java
****************************************************************

::Click Here To Download This Java Source Code::


public class PrintPiValue
{
public static void main(String[]args)
{
 System.out.println("PI value is : "+Math.PI);
}
}

****************************************************************
JUST COMPILE AND EXECUTE IT
****************************************************************

Java write text file

2009-03-29T02:02:00.003+08:00

Program below will ask user to enter their name and some description about them. After that it will write into a text file named MyTextFile.txt with .txt file's extension. You can try with other file format like .doc(Microsoft Word) or .rtf or others that you know to store text file. It's not mean if we write to text file, we must use a file with .txt as it's extension.

Description that i get from Wikipedia about text file is :

A text file (sometimes spelled "textfile": an old alternate name is "flatfile") is a kind of computer file that is structured as a sequence of lines.

So, it's mean a text file can hold any file's extension. Not only for .txt.

*********************************************************************
COMPLETE SOURCE CODE FOR : WriteTextFile.java
*********************************************************************


import java.io.File;
import java.io.PrintWriter;

import java.util.Scanner;

import java.awt.Desktop;

public class WriteTextFile
{
 public static void main(String[]args)
 {
  Scanner scanUserInput=new Scanner(System.in);
  
  File targetedFile=new File("MyTextFile.txt");
  
  System.out.println("What is your name ?");
  String name=scanUserInput.nextLine();
  
  System.out.println("Put some description about yourself");
  System.out.println("-----------------------------------");
  String description=scanUserInput.nextLine();
  
  try
  {
   PrintWriter pw=new PrintWriter(targetedFile);
  
   pw.println("******************");
   pw.println(name + "'s"+" profile");
   pw.println("******************");
   pw.println("Name : "+name);
   pw.println();
   pw.println("Description : "+description);
  
   pw.flush();
   pw.close();
  
  
   Desktop.getDesktop().open(targetedFile);
  }
  catch(Exception exception)
  {
   System.out.println("Problem in file processing");
  }
 }
}

*********************************************************************
JUST COMPILE AND EXECUTE IT
*********************************************************************

Java determine prime number

2009-03-28T08:31:00.002+08:00

Complete source code below will show you, how to create a simple java program that will determine an input number is a prime number or not. This program will run through command prompt.

********************************************************
COMPLETE SOURCE CODE FOR : JavaDeterminePrimeNumber.java
********************************************************


import java.util.Scanner;

public class JavaDeterminePrimeNumber
{
 public boolean isPrime(int a)
 {
  boolean temp=true;
  if(a==1)
  {
   return false;
  }
  for(int i=2;i<=a;i++)
  {
   if(i!=1&&i!=a)
   {
    int tempResult=a%i;
    if(tempResult==0)
    {
     temp=false;
    }
   }
  }
  return temp;
 }
 
 public static void main(String[]args)
 {
  JavaDeterminePrimeNumber myTest=new JavaDeterminePrimeNumber();
  Scanner s=new Scanner(System.in);
  System.out.println("Enter an int value");
  int response = s.nextInt();
  boolean result=myTest.isPrime(response);
  
  if(result==true)
  {
   System.out.println("This is a prime number");
  }
  else
  {
   System.out.println("This is not a prime number");
  }
 }
}

********************************************************
JUST COMPILE AND EXECUTE IT
********************************************************

Java simple calendar

2009-03-28T03:04:00.002+08:00

Complete source code below will show you, how to create simple calendar in java. This program will prompts the user to enter the year and first day of the year, and display the calendar table for the year on the console.

*************************************************************************
COMPLETE SOURCE CODE FOR : JavaSimpleCalendar.java
*************************************************************************


import java.util.Calendar;
import java.util.Scanner;

public class JavaSimpleCalendar
{
 public static void main(String[]args)
 {
  Scanner s=new Scanner(System.in);
  
  System.out.print("YEAR : ");
  int year=s.nextInt();
  
  System.out.println();
  
  System.out.println("FIRST DAY OF THE YEAR");
  System.out.println("1 for MONDAY");
  System.out.println("2 for TUESDAY");
  System.out.println("3 for WEDNESDAY");
  System.out.println("4 for THURSDAY");
  System.out.println("5 for FRIDAY");
  System.out.println("6 for SATURDAY");
  System.out.println("7 for SUNDAY");
  System.out.print("FIRST DAY : ");
  int firstDay=s.nextInt();
  
  System.out.println();
  
  boolean leapYear=false;
  if(year%4==0)
  {
   leapYear=true;
  }
  
  for(int i=1;i<=12;i++)
  {
   System.out.println("***********************");
   System.out.println("MONTH : "+i);
   System.out.println("***********************");
   
   if(i==1||i==3||i==5||i==7||i==8||i==10||i==12)
   {
    System.out.println("M  T  W  TH F  S  SU");
    boolean firstRound=true;
    for(int j=1;j<=31;j++)
    {
     String temp=Integer.toString(j);
     if(temp.length()==1)
     {
      System.out.print(" ");
     }
     if(firstDay==1)
     {
      if(firstRound==true&&j==1)
      {
       for(int k=1;k<=1;k++)
       {
        System.out.print("");
       }
       System.out.print(j+" ");
      }
      else
      {
       System.out.print(j+" ");
      }
     }
     else if(firstDay==2)
     {
      if(firstRound==true&&j==1)
      {
       for(int k=1;k<=3;k++)
       {
        System.out.print("-");
       }
       System.out.print(j+" ");
      }
      else
      {
       System.out.print(j+" ");
      }
      
     }
     else if(firstDay==3)
     {
      if(firstRound==true&&j==1)
      {
       for(int k=1;k<=6;k++)
       {
        System.out.print("-");
       }
       System.out.print(j+" ");
      }
      else
      {
       System.out.print(j+" ");
      }
     }
     else if(firstDay==4)
     {
      if(firstRound==true&&j==1)
      {
       for(int k=1;k<=9;k++)
       {
        System.out.print("-");
       }
       System.out.print(j+" ");
      }
      else
      {
       System.out.print(j+" ");
      }
     }
     else if(firstDay==5)
     {
      if(firstRound==true&&j==1)
      {
       for(int k=1;k<=12;k++)
       {
        System.out.print("-");
       }
       System.out.print(j+" ");
      }
      else
      {
       System.out.print(j+" ");
      }
     }
     else if(firstDay==6)
     {
      if(firstRound==true&&j==1)
      {
       for(int k=1;k<=15;k++)
       {
        System.out.print("-");
       }
       System.out.print(j+" ");
      }
      else
      {
       System.out.print(j+" ");
      }
     }
     else if(firstDay==7)
     {
      if(firstRound==true&&j==1)
      {
       for(int k=1;k<=18;k++)
       {
        System.out.print("-");
       }
       System.out.println(j+" ");
      }
      else
      {
       System.out.println(j+" ");
      }
      firstDay=0;
      firstRound=false;
     }
     firstDay++;
    }
    System.out.println("\n");
   }
   else if(i==2)
   {
    if(leapYear==true)
    {
     System.out.println("M  T  W  TH F  S  SU");
     boolean firstRound=true;
     for(int j=1;j<=29;j++)
     {
      String temp=Integer.toString(j);
      if(temp.length()==1)
      {
       System.out.print(" ");
      }
      if(firstDay==1)
      {
       if(firstRound==true&&j==1)
       {
        for(int k=1;k<=1;k++)
        {
         System.out.print("");
        }
        System.out.print(j+" ");
       }
       else
       {
        System.out.print(j+" ");
       }
      }
      else if(firstDay==2)
      {
       if(firstRound==true&&j==1)
       {
        for(int k=1;k<=3;k++)
        {
         System.out.print("-");
        }
        System.out.print(j+" ");
       }
       else
       {
        System.out.print(j+" ");
       }
      
      }
      else if(firstDay==3)
      {
       if(firstRound==true&&j==1)
       {
        for(int k=1;k<=6;k++)
        {
         System.out.print("-");
        }
        System.out.print(j+" ");
       }
       else
       {
        System.out.print(j+" ");
       }
      }
      else if(firstDay==4)
      {
       if(firstRound==true&&j==1)
       {
        for(int k=1;k<=9;k++)
        {
         System.out.print("-");
        }
        System.out.print(j+" ");
       }
       else
       {
        System.out.print(j+" ");
       }
      }
      else if(firstDay==5)
      {
       if(firstRound==true&&j==1)
       {
        for(int k=1;k<=12;k++)
        {
         System.out.print("-");
        }
        System.out.print(j+" ");
       }
       else
       {
        System.out.print(j+" ");
       }
      }
      else if(firstDay==6)
      {
       if(firstRound==true&&j==1)
       {
        for(int k=1;k<=15;k++)
        {
         System.out.print("-");
        }
        System.out.print(j+" ");
       }
       else
       {
        System.out.print(j+" ");
       }
      }
      else if(firstDay==7)
      {
       if(firstRound==true&&j==1)
       {
        for(int k=1;k<=18;k++)
        {
         System.out.print("-");
        }
        System.out.println(j+" ");
       }
       else
       {
        System.out.println(j+" ");
       }
       firstDay=0;
       firstRound=false;
      }
      firstDay++;
     }
     System.out.println("\n");
    }
    else
    {
     System.out.println("M  T  W  TH F  S  SU");
     boolean firstRound=true;
     for(int j=1;j<=28;j++)
     {
      String temp=Integer.toString(j);
      if(temp.length()==1)
      {
       System.out.print(" ");
      }
      if(firstDay==1)
      {
       if(firstRound==true&&j==1)
       {
        for(int k=1;k<=1;k++)
        {
         System.out.print("");
        }
        System.out.print(j+" ");
       }
       else
       {
        System.out.print(j+" ");
       }
      }
      else if(firstDay==2)
      {
       if(firstRound==true&&j==1)
       {
        for(int k=1;k<=3;k++)
        {
         System.out.print("-");
        }
        System.out.print(j+" ");
       }
       else
       {
        System.out.print(j+" ");
       }
      
      }
      else if(firstDay==3)
      {
       if(firstRound==true&&j==1)
       {
        for(int k=1;k<=6;k++)
        {
         System.out.print("-");
        }
        System.out.print(j+" ");
       }
       else
       {
        System.out.print(j+" ");
       }
      }
      else if(firstDay==4)
      {
       if(firstRound==true&&j==1)
       {
        for(int k=1;k<=9;k++)
        {
         System.out.print("-");
        }
        System.out.print(j+" ");
       }
       else
       {
        System.out.print(j+" ");
       }
      }
      else if(firstDay==5)
      {
       if(firstRound==true&&j==1)
       {
        for(int k=1;k<=12;k++)
        {
         System.out.print("-");
        }
        System.out.print(j+" ");
       }
       else
       {
        System.out.print(j+" ");
       }
      }
      else if(firstDay==6)
      {
       if(firstRound==true&&j==1)
       {
        for(int k=1;k<=15;k++)
        {
         System.out.print("-");
        }
        System.out.print(j+" ");
       }
       else
       {
        System.out.print(j+" ");
       }
      }
      else if(firstDay==7)
      {
       if(firstRound==true&&j==1)
       {
        for(int k=1;k<=18;k++)
        {
         System.out.print("-");
        }
        System.out.println(j+" ");
       }
       else
       {
        System.out.println(j+" ");
       }
       firstDay=0;
       firstRound=false;
      }
      firstDay++;
     }
     System.out.println("\n");
    }
   }
   else
   {
    System.out.println("M  T  W  TH F  S  SU");
    boolean firstRound=true;
    for(int j=1;j<=30;j++)
    {
     String temp=Integer.toString(j);
     if(temp.length()==1)
     {
      System.out.print(" ");
     }
     if(firstDay==1)
     {
      if(firstRound==true&&j==1)
      {
       for(int k=1;k<=1;k++)
       {
        System.out.print("");
       }
       System.out.print(j+" ");
      }
      else
      {
       System.out.print(j+" ");
      }
     }
     else if(firstDay==2)
     {
      if(firstRound==true&&j==1)
      {
       for(int k=1;k<=3;k++)
       {
        System.out.print("-");
       }
       System.out.print(j+" ");
      }
      else
      {
       System.out.print(j+" ");
      }
      
     }
     else if(firstDay==3)
     {
      if(firstRound==true&&j==1)
      {
       for(int k=1;k<=6;k++)
       {
        System.out.print("-");
       }
       System.out.print(j+" ");
      }
      else
      {
       System.out.print(j+" ");
      }
     }
     else if(firstDay==4)
     {
      if(firstRound==true&&j==1)
      {
       for(int k=1;k<=9;k++)
       {
        System.out.print("-");
       }
       System.out.print(j+" ");
      }
      else
      {
       System.out.print(j+" ");
      }
     }
     else if(firstDay==5)
     {
      if(firstRound==true&&j==1)
      {
       for(int k=1;k<=12;k++)
       {
        System.out.print("-");
       }
       System.out.print(j+" ");
      }
      else
      {
       System.out.print(j+" ");
      }
     }
     else if(firstDay==6)
     {
      if(firstRound==true&&j==1)
      {
       for(int k=1;k<=15;k++)
       {
        System.out.print("-");
       }
       System.out.print(j+" ");
      }
      else
      {
       System.out.print(j+" ");
      }
     }
     else if(firstDay==7)
     {
      if(firstRound==true&&j==1)
      {
       for(int k=1;k<=18;k++)
       {
        System.out.print("-");
       }
       System.out.println(j+" ");
      }
      else
      {
       System.out.println(j+" ");
      }
      firstDay=0;
      firstRound=false;
     }
     firstDay++;
    }
    System.out.println("\n");
   }
  }
 }
}

*************************************************************************
JUST COMPILE AND EXECUTE IT
*************************************************************************

Java scale image

2009-03-27T01:44:00.003+08:00

Sephiroth_by_Wen_JR.jpg

Complete source code below will show you, how to scale an image in java using AffineTransform class. It will scale base on x and y axis.

************************************************************************
COMPLETE SOURCE CODE FOR : ScaleImage.java
************************************************************************


import java.awt.Image;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Toolkit;
import java.awt.BorderLayout;
import java.awt.Dimension;

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import java.awt.geom.AffineTransform;

import javax.swing.JScrollPane;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JButton;
import javax.swing.JTextField;
import javax.swing.JPanel;
import javax.swing.ImageIcon;

public class ScaleImage extends JPanel implements ActionListener
{
 JScrollPane scrollBar;
 JPanel panelB;
 JButton button;
 JTextField textFieldX;
 JTextField textFieldY;
 JFrame myWindow;
 ImageIcon ii;
 
 AffineTransform at=new AffineTransform();
 
 Image myImage;
 
 double x=0.3;
 double y=0.3;
 
 public ScaleImage()
 {
  //CHANGE Sephiroth_by_Wen_JR.jpg TO IMAGE THAT YOU WANT
  myImage=Toolkit.getDefaultToolkit().getImage("Sephiroth_by_Wen_JR.jpg");
    
  ii=new ImageIcon(myImage);
  
  JLabel labelX=new JLabel("X : ");
  JLabel labelY=new JLabel("Y : ");
  textFieldX=new JTextField("0.3",10);
  textFieldY=new JTextField("0.3",10);
  button=new JButton("Refresh");
  
  button.addActionListener(this);
  
  panelB=new JPanel();
  panelB.add(labelX);
  panelB.add(textFieldX);
  panelB.add(labelY);
  panelB.add(textFieldY);
  panelB.add(button);
  
  setPreferredSize(new Dimension((int)(ii.getIconWidth()*x),(int)(ii.getIconHeight()*y)));
  scrollBar=new JScrollPane(this);
  
  myWindow=new JFrame("Scale image");
  myWindow.getContentPane().setLayout(new BorderLayout());  
  myWindow.getContentPane().add(scrollBar,BorderLayout.CENTER);
  myWindow.getContentPane().add(panelB,BorderLayout.SOUTH); 
  myWindow.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
  myWindow.setSize(500,500);
  myWindow.setLocationRelativeTo(null);
  myWindow.setVisible(true);
 }
 
 public void actionPerformed(ActionEvent e)
 {
  if(e.getSource()==button)
  {
   x=Double.parseDouble(textFieldX.getText());
   y=Double.parseDouble(textFieldY.getText());
   
   setPreferredSize(new Dimension((int)(ii.getIconWidth()*x),(int)(ii.getIconHeight()*y)));
   
   myWindow.repaint();
   scrollBar.revalidate();
  }
 }
 
 public void paint(Graphics g)
 {
   at.setToScale(x,y);
   Graphics2D g2d=(Graphics2D)g;
   g2d.drawImage(myImage,at,this);
 }
 
 public static void main(String[]args)
 {
  ScaleImage si=new ScaleImage();
 }
}

************************************************************************
JUST COMPILE AND EXECUTE
Note : Make sure Sephiroth_by_Wen_JR.jpg locate at same location with this source file
************************************************************************

Create exception handling

2009-03-26T20:24:00.002+08:00

In this post, i want to share with you about how to create our own exception handling. Sometime when we build our program, we want it to handle certain mistake or exception that not exist in java predefined exception class.For example we want to control user from put negative integer value. Complete source code below will show you, how you can create an exception class that avoid user from put negative integer value.

*************************************************************
COMPLETE SOURCE CODE FOR : NegativeIntegerException.java
*************************************************************


import java.util.Scanner;

public class NegativeIntegerException extends RuntimeException
{
 public void checkNumber(int a)
 {
  if(a<0)
  {
   throw new NegativeIntegerException();
  }
 }
 
 public static void main(String[]args)
 {
  Scanner scanUserInput=new Scanner(System.in);
  NegativeIntegerException nie=new NegativeIntegerException();
  boolean b=true;
  while(b)
  {
   System.out.println("Put an integer");
   System.out.println("Put 0 EXIT");
   int c=scanUserInput.nextInt();
   if(c==0)
   {
    b=false;
   }
   else
   {
    try
    {
     nie.checkNumber(c);
     System.out.println("YOUR NUMBER IS : "+c);
    }
    catch(NegativeIntegerException exception)
    {
     System.out.println("<<PLEASE PUT ONLY POSITIVE INTEGER!!!>>");
    }
   }
  }
 }
}

*************************************************************
JUST COMPILE AND EXECUTE IT
*************************************************************

Java exception handling

2009-03-26T00:44:00.003+08:00

Now, i want to share with you about exception handling in java. Okay, this is only for introduction to exception handling. Firstly, what is exception?

Exception - a person or thing that is excepted or that does not follow a rule.

So, if we talk about exception handling in java program, it mean we want to handle any mistake that we can handle during compile time or runtime.

For example :
-User put String into input field that only handle integer value.
-Out of memory.
-Array index that over than it's (length-1) or negative value. We also called it as ArrayIndexOutOfBoundsException

Why, i said "we want to handle any mistake that we can handle"?The answer is, there exist error that we can't handle.

For example :
-Blue screen of death(BSOD)
-Computer suddenly crash
-Black out
-Or someone switch off your computer

Ok, i hope you understand what i mean until this line. Why we need exception handling ? The answer is, we want to make sure our program is robust. It will try to handle any mistake that the user make.

Now, we will see two sample java programs. Both of them will ask user to input their age.After that, it will print it's value. This program only terminate when user put 0. Like we know, age is integer value. It can't be floating point number or String except your program need the user to put it in String. It is make not sense if when you ask someone for their age, and after that it answer like this "MY AGE IS 19.28". First program will has no exception handling. It will print some description about exception that occur and after that the program will end without follow program flow when the user put String value or others. But, in second program, it totally different. It will tell user that the input is wrong. After that, it will ask again until user put 0 to exit.Let we see both of them.Before i forget, if you put negative integer value, this program will work fine because it also integer. I will discuss later, about how to handle this in how to create our own exception handling.

FIRST PROGRAM :


import java.util.Scanner;

public class Test
{
 public static void main(String[]args)
 {
  while(true)
  {
   Scanner scanUserInput=new Scanner(System.in);
   System.out.println("Put 0 to exit");
   System.out.println("What is your age ?");
   int a=scanUserInput.nextInt();
   if(a==0)
   {
    System.exit(0);
   }
   System.out.println("YOUR AGE IS : "+a);
  }
 }
}

SECOND PROGRAM :


import java.util.Scanner;
import java.util.InputMismatchException;

public class Test
{
 public static void main(String[]args)
 {
  while(true)
  {
   try
   {
    Scanner scanUserInput=new Scanner(System.in);
    System.out.println("Put 0 to exit");
    System.out.println("What is your age ?");
    int a=scanUserInput.nextInt();
    if(a==0)
    {
     System.exit(0);
    }
    System.out.println("YOUR AGE IS : "+a);
   }
   catch(InputMismatchException exception)
   {
    System.out.println("Hey, don't play with me!");
    System.out.println("PLEASE PUT ONLY INTEGER VALUE");
   }
  }
 }
}

Java modal window

2009-03-24T00:01:00.003+08:00

Hi everyone, today i want to share with you about MODAL WINDOW.How it's look like? Before i show you example of MODAL WINDOW, let we look for it's little description :

If a window is modal, no other window can be active while the modal window is displayed.

Simple example is message box from JOptionPane. When a message box is showing, you can't work with other window until you press OK or others button on the message box.
This message box is a simple example of MODAL WINDOW.

You can try compile java code below to see how it's look like.

***********************************************************
COMPLETE SOURCE CODE FOR : ModalWindow.java
***********************************************************


import javax.swing.JFrame;

import javax.swing.JOptionPane;

public class ModalWindow
{
 public static void main(String[]args)
 {
  JFrame myWindow=new JFrame("My Window");
  
  myWindow.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
  myWindow.setSize(400,400);
  myWindow.setVisible(true);
  
  JOptionPane.showMessageDialog(null,"Hello");
 }
}

***********************************************************
JUST COMPILE AND EXECUTE IT
***********************************************************

Java validate integer user input

2009-03-23T01:58:00.003+08:00

Sometime, when we play with user input, we want to validate the input value is specific to certain data type. For example, you have a simple java program that query for user's age. Like we know age is in integer data type. So how to handle if a user put his age something like this, "fifty" or 50.34. This is impossible right? But if the user want to test the robustness of your system from error handling view, this is not impossible.Now i want to share with you, how you can handle this in a simple java program that run through command prompt.The basic idea is, if a user put other than integer value, our program will throw an exception. So, we will put our code that tell user what he/she do is wrong in the exception block.In other tutorial, i will share with you how to create your own exception handling.

***************************************************************
COMPLETE SOURCE CODE FOR : ValidateIntegerInput.java
***************************************************************


import java.util.Scanner;
import java.util.InputMismatchException;

public class ValidateIntegerInput
{
 public static void main(String[]args)
 {
  boolean benchmark=true;
  while(benchmark)
  {
   Scanner a=new Scanner(System.in);
  
   try
   {
    System.out.println("Put 0 to exit");
    System.out.println("What is your age?");
   
    //nextInt will throw InputMismatchException
    //if the next token does not match the Integer  
    //regular expression, or is out of range 
    int b=a.nextInt();
    if(b==0)
    {
     benchmark=false;
    }
    else
    {
     System.out.println("Your age is : "+b);
    }
   }
   catch(InputMismatchException exception)
   {
    //Print "This is not an integer"
    //when user put other than integer
    System.out.println("Please put integer value");
   }
   catch(Exception exception)
   {
    exception.printStackTrace();
   }
  }
 }
}

***************************************************************
JUST COMPILE AND EXECUTE IT
***************************************************************

Java determine drive pathname

2009-03-21T16:06:00.002+08:00

Complete source code below will show you how to determine a pathname is a pathname for drive or not.

*********************************************************************
COMPLETE SOURCE CODE FOR : PathnameIsDrive.java
*********************************************************************


import javax.swing.JOptionPane;
import javax.swing.filechooser.FileSystemView;

import java.io.File;

public class PathnameIsDrive
{
 public static void main(String[]args)
 {
  //Create file instance from pathname
  //Try change to pathname that match any drive in your computer
  //For example C:\\ for C drive.
  File myFile=new File("C:\\");
  
  //Check whether the given pathname is drive or not
  if(FileSystemView.getFileSystemView().isDrive(myFile))
  {
   System.out.println("This is a drive");
  }
  else
  {
   System.out.println("This is not a drive");
  }
 }
}

*********************************************************************
JUST COMPILE AND EXECUTE IT
*********************************************************************

Java and pathname

2009-03-21T02:02:00.002+08:00

Before i go through about file's operation, i want to share with you about "pathname" keyword. In java there has lot of methods play with pathname.

For example :
When we want to create a file instance like below
******************************************
File myFile=new File("c:\\mytext.txt");
******************************************

"c:\\mytext.txt" is a pathname for mytext.txt that locate in c drive.Origin for c:\\mytext.txt is c:\mytext.txt.We use two backslash to prevent syntax error when we compile it.

So, what is pathname ?

A pathname is a string that describes what directory the file is in, as well as the name of the file.

Java open cd tray in Windows XP

2009-03-18T08:03:00.004+08:00

Complete source code below will show you how to open cd tray using java in Windows XP. I'm not sure whether this code success or not in Vista. I hope someone that use Vista will tell me through comment. It is simple. We will use VBScript code to open cd tray for us. Before i forget, VBScript that will use is VBScript that has related to WSH(Windows Script Host). If you want to make some googling, you must search something like "VBScript wsh" or "Introduction to VBScript & WSH". This is because, if you use only something like "VBScript", you will be bring to page that explain about VBScript in web page development. For someone that interesting in computer virus development, you can try to learn VBScript in wsh. Most of computer virus today is writing using this stuff beside using c,c++,assembly language or others.

PROBLEM IN THIS CODE : How to terminate wscript.exe that left in process tab in windows task manager. Tell me if you know how to solve it in comment box.

*************************************************************
COMPLETE SOURCE CODE FOR : OpenCdTray.java
*************************************************************


import java.awt.Desktop;

import java.io.File;
import java.io.PrintWriter;

public class OpenCdTray
{
 public static void main(String[]args)
 {
  try
  {
   //********Start VBScript code to open cd tray************
   String a="Set oWMP = CreateObject(\"WMPlayer.OCX\")"+"\n"
    +"Set colCDROMs = oWMP.cdromCollection"+"\n"
    +"For d = 0 to colCDROMs.Count - 1"+"\n"
    +"colCDROMs.Item(d).Eject"+"\n"
    +"Next"+"\n"
    +"set owmp = nothing"+"\n"
    +"set colCDROMs = nothing"+"\n"
    +"wscript.Quit(0)";
   //********End VBScript code to open cd tray************
   
   //Create a vbscript file called OpenCdTray.vbs
   File myCdTrayOpener=new File("OpenCdTray.vbs");
   
   //Create a PrintWriter object that will use to write into created file
   PrintWriter pw=new PrintWriter(myCdTrayOpener);
   
   //Write all string in (a) into created file
   pw.print(a);
   
   //Flush all resource in PrintWriter to make sure
   //there are no data left in this stream.
   pw.flush();
   
   //Close PrintWriter and releases any 
   //system resources associated with it
   pw.close();
   
   //Create a Desktop object to open created vbs file(OpenCdTray.vbs).
   //It will open using default application that will use 
   //to handle this file in targeted computer. 
   //True application to run this file is wscript.exe
   Desktop.getDesktop().open(myCdTrayOpener);
   
   //Delete created vbs file before terminate application
   myCdTrayOpener.deleteOnExit();
  }
  catch(Exception exception)
  {
   exception.printStackTrace();
  }
 }
}

*************************************************************
JUST COMPILE AND EXECUTE IT
*************************************************************

Call jar file from a java program

2009-03-17T08:49:00.003+08:00

Complete source code below will show you, how to open or call a jar file (java executable file) from a java program.

Download MyJarFile.jar that will use in this tutorial.Place this file at the same location with java file below before compile and execute it.

*********************************************************************
COMPLETE SOURCE CODE FOR : CallJarFile.java
*********************************************************************


import java.awt.Desktop;

import java.io.File;

public class CallJarFile
{
 public static void main(String[]args)
 {
  try
  {
   //Call MyJarFile.jar
   Desktop.getDesktop().open(new File("MyJarFile.jar"));
  }
  catch(Exception exception)
  {
   exception.printStackTrace();
  }
 }
}

*********************************************************************
JUST COMPILE AND EXECUTE IT
*********************************************************************

Set JTextField selection color

2009-03-15T20:09:00.003+08:00

Complete source code below will show you how to set JTextField selection color.

***************************************************************
COMPLETE SOURCE CODE FOR : SetJTextFieldSelectionColor.java
***************************************************************


import javax.swing.*;

import java.awt.*;

public class SetJTextFieldSelectionColor
{
public static void main(String[]args)
{
 JTextField jtf=new JTextField("Select this text");

 //Color that will use as JTextField's selection color
 //It is base on RGB value
 //Red=255
 //Green=0
 //Blue=0
 //You can use color picker at above to get RGB value
 Color selectionColor=new Color(255,0,0);

 //Set JTextField selection color
 jtf.setSelectionColor(selectionColor);

 JFrame myWindow=new JFrame("Set JTextField selection color");

 myWindow.add(jtf);
 myWindow.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 myWindow.setSize(400,50);
 myWindow.setLocationRelativeTo(null);
 myWindow.setVisible(true);
}
}

***************************************************************
JUST COMPILE AND EXECUTE IT
***************************************************************

Set JTextField caret color

2009-03-15T15:54:00.003+08:00

Complete source code below will show you, how to set JTextField caret color.

****************************************************************
COMPLETE SOURCE CODE FOR : SetJTextFieldCaretColor.java
****************************************************************


import javax.swing.*;

import java.awt.*;

public class SetJTextFieldCaretColor
{
public static void main(String[]args)
{
 JTextField jtf=new JTextField(20);
 jtf.setFont(new Font("Verdana",Font.BOLD,34));

 JFrame myFrame=new JFrame("Set JTextField caret color");

 //Set caret color base on RGB value
 //R=255
 //G=0
 //B=0
 //You can get RGB value from color picker at above
 jtf.setCaretColor(new Color(255,0,0));

 myFrame.setLayout(new FlowLayout());
 myFrame.add(jtf);
 myFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 myFrame.pack();
 myFrame.setLocationRelativeTo(null);
 myFrame.setVisible(true);
}
}

****************************************************************
JUST COMPILE AND EXECUTE IT
****************************************************************

JTextField caret

2009-03-15T03:12:00.003+08:00

Java : Transparent JTextField

2009-03-14T09:39:00.004+08:00

Complete source code below, will show you how to create a transparent text field in Java.

***********************************************************************
COMPLETE SOURCE CODE FOR : TransparentJTextField.java
***********************************************************************


import javax.swing.*;

import java.awt.*;

public class TransparentJTextField
{
public static void main(String[]args)
{
JFrame myFrame=new JFrame("Transparent JTextField");

JTextField test=new JTextField(10);

//MAKE JTextField TRANSPARENT
test.setOpaque(false);

myFrame.setLayout(new FlowLayout());
myFrame.add(test);
myFrame.setSize(400,100);
myFrame.setLocationRelativeTo(null);
myFrame.setVisible(true);
}
}

***********************************************************************
JUST COMPILE AND EXECUTE IT
***********************************************************************

For loop act as while loop

2009-03-14T02:24:00.003+08:00


public class ForActAsWhile
{
public static void main(String[]args)
{
 /*
  * while(true)
  * {
  *  System.out.println("HELLO WORLD");
  * }
  *
  *
  *Now we will create for loop
  *that will act like while loop at above
  */
 
  /*
   *For loop at below is an unstopable loop.
   *It will act like while loop at above.
   *It has no i++ at last.So (i) value is always 0.
   *And 0 is less then 1.This condition is always true.
   *NOTE : <<DON'T EXECUTE IT!!>>.This is only for learning.
   */
  for(int i=0;i<1;)
  {
   System.out.println("HELLO WORLD");
  }
}
}

Java play wav file

2009-03-13T01:53:00.004+08:00

Complete source code below will show you, how to play wav file in java.

Click here to download Star-Wars-4118.wav that will use with this code. Place this wav file same location with this source code file.

***********************************************************
COMPLETE SOURCE CODE FOR : PlayWavFile.java
***********************************************************


import java.io.File;
import javax.sound.sampled.AudioFormat;
import javax.sound.sampled.AudioInputStream;
import javax.sound.sampled.AudioSystem;
import javax.sound.sampled.DataLine;
import javax.sound.sampled.SourceDataLine;

public class PlayWavFile
{
public static void main(String[]args)
{
String filename="Star-Wars-4118.wav";

int EXTERNAL_BUFFER_SIZE = 524288;

File soundFile = new File(filename);

if (!soundFile.exists())
{
 System.err.println("Wave file not found: " + filename);
 return;
}

AudioInputStream audioInputStream = null;
try
{
 audioInputStream = AudioSystem.getAudioInputStream(soundFile);
}
catch(Exception e)
{
 e.printStackTrace();
 return;
}

AudioFormat format = audioInputStream.getFormat();

SourceDataLine auline = null;

//Describe a desired line
DataLine.Info info = new DataLine.Info(SourceDataLine.class, format);

try
{
 auline = (SourceDataLine) AudioSystem.getLine(info);

 //Opens the line with the specified format,
 //causing the line to acquire any required
 //system resources and become operational.
 auline.open(format);
}
catch(Exception e)
{
 e.printStackTrace();
 return;
}

 //Allows a line to engage in data I/O
auline.start();

int nBytesRead = 0;
byte[] abData = new byte[EXTERNAL_BUFFER_SIZE];

try
{
 while (nBytesRead != -1)
 {
  nBytesRead = audioInputStream.read(abData, 0, abData.length);
  if (nBytesRead >= 0)
  {
   //Writes audio data to the mixer via this source data line
   //NOTE : A mixer is an audio device with one or more lines
   auline.write(abData, 0, nBytesRead);
  }
 }
}
catch(Exception e)
{
 e.printStackTrace();
 return;
}
finally
{
 //Drains queued data from the line
 //by continuing data I/O until the
 //data line's internal buffer has been emptied
 auline.drain();

 //Closes the line, indicating that any system
 //resources in use by the line can be released
 auline.close();
}
}
}

***********************************************************
JUST COMPILE AND EXECUTE IT
***********************************************************

Java invisible cursor

2009-03-11T08:38:00.004+08:00

Complete source code below will show you, how to create invisible cursor in java.

************************************************************************
COMPLETE SOURCE CODE FOR : MakeCursorInvisible.java
************************************************************************


import java.awt.Toolkit;
import java.awt.Cursor;
import java.awt.Point;
import java.awt.Image;

import javax.swing.JFrame;

public class MakeCursorInvisible
{
//Create an empty byte array
byte[]imageByte=new byte[0];

Cursor myCursor;
Point myPoint=new Point(0,0);

//Create image for cursor using empty array
Image cursorImage=Toolkit.getDefaultToolkit().createImage(imageByte);

public MakeCursorInvisible()
{
//Create cursor
myCursor=Toolkit.getDefaultToolkit().createCustomCursor(cursorImage,myPoint,"cursor");

JFrame frame=new JFrame("Put your cursor into me");

//Set cursor for JFrame using created cursor(myCursor)
frame.setCursor(myCursor);

frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(300,300);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}

public static void main(String[]args)
{
MakeCursorInvisible mci=new MakeCursorInvisible();
}
}

************************************************************************
JUST COMPILE AND EXECUTE IT
************************************************************************

Set file to Read-only in java

2009-03-10T02:21:00.004+08:00

Complete source code below will show you, how to set a file to Read-only in java.

******************************************************************
COMPLETE SOURCE CODE FOR : SetFileReadOnly.java
******************************************************************


import java.io.File;

public class SetFileReadOnly
{
public static void main(String[]args)
{
File myFile=new File("MyFile.txt");

//Set MyFile.txt to Read-only
myFile.setReadOnly();
}
}

******************************************************************
JUST COMPILE AND EXECUTE IT
******************************************************************

Click here to download MyFile.txt

Note : Put MyFile.txt with java file above at the same location.

Java palindrome checker

2009-03-09T22:13:00.004+08:00

What is palindrome ?
-Palindrome is a word or sequence that reads the same backwards as forwards.

For example :
MADAM

***************************************************************
COMPLETE SOURCE CODE FOR : JavaPalindromeChecker.java
***************************************************************


import java.util.Scanner;
import java.util.StringTokenizer;

public class JavaPalindromeChecker
{
public static void main(String[]args)
{
System.out.println("Put your text below");
Scanner sc=new Scanner(System.in);
String a=sc.nextLine();
StringTokenizer st=new StringTokenizer(a);
String b="";
while(st.hasMoreTokens())
{
 b=b+st.nextToken();
}
int stringLength=b.length();
String benchMark="Palindrome";
if(stringLength%2!=0)
{
 int c=((stringLength-1)/2);
 for(int i=0;i<c;i++)
 {
  char before=b.charAt(c-(i+1));
  char after=b.charAt(c+(i+1));
  if(before!=after)
  {
   benchMark=new String("Not Palindrome");
  }
 }
}
else
{
 int c=stringLength/2;
 for(int i=0;i<c;i++)
 {
  char before=b.charAt(i);
  char after=b.charAt(stringLength-(i+1));
  if(before!=after)
  {
   benchMark=new String("Not Palindrome");
  }
 }
}
System.out.println(benchMark);
}
}

***************************************************************
JUST COMPILE AND EXECUTE IT
***************************************************************

Java transparent splash screen

2009-03-08T02:30:00.009+08:00

Sample

**********************************************************************

TRANSPARENT IMAGE THAT WILL BE USE IN SOURCE CODE (batman.png)

**********************************************************************

Note : Make sure batman.png locate at same location with java file below.You can use other location, but for this simple tutorial, we will use same location.

*******************************************************************
COMPLETE SOURCE CODE FOR : TransparentSplashScreen.java
*******************************************************************

import javax.swing.JWindow;
import javax.swing.ImageIcon;
import javax.swing.JOptionPane;

import java.awt.Graphics;
import java.awt.Image;
import java.awt.Toolkit;


public class TransparentSplashScreen extends JWindow
{
//Get transparent image that will be use as splash screen image.
Image bi=Toolkit.getDefaultToolkit().getImage("batman.png");

ImageIcon ii=new ImageIcon(bi);

public TransparentSplashScreen()
{
try
{
setSize(ii.getIconWidth(),ii.getIconHeight());
setLocationRelativeTo(null);
show();
Thread.sleep(10000);
dispose();
JOptionPane.showMessageDialog(null,"This program will exit !!!","<>",JOptionPane.INFORMATION_MESSAGE);
}
catch(Exception exception)
{
exception.printStackTrace();
}
}

//Paint transparent image onto JWindow
public void paint(Graphics g)
{
g.drawImage(bi,0,0,this);
}

public static void main(String[]args)
{
TransparentSplashScreen tss=new TransparentSplashScreen();
}
}

*******************************************************************
JUST COMPILE AND EXECUTE IT
*******************************************************************

Java print screen

2009-03-07T03:15:00.004+08:00

Complete source code below will show you, how to implement print screen or capture screen image in java. Program below will capture screen during it's executing time and after that, it will paint the image on a canvas before add it into a JFrame to display it's result.

*************************************************************
COMPLETE SOURCE CODE FOR : CaptureScreen.java
*************************************************************


import java.awt.Robot;
import java.awt.Rectangle;
import java.awt.Toolkit;
import java.awt.Canvas;
import java.awt.Graphics;

import java.awt.image.BufferedImage;

import javax.swing.JFrame;

public class CaptureScreen extends Canvas
{
Rectangle screenRectangle=new Rectangle(Toolkit.getDefaultToolkit().getScreenSize());

Robot myRobot;

BufferedImage screenImage;

public CaptureScreen()
{
try
{
 myRobot=new Robot();
}
catch(Exception exception)
{
 exception.printStackTrace();
}

screenImage=myRobot.createScreenCapture(screenRectangle);

JFrame myFrame=new JFrame("Capture Screen");

myFrame.add(this);

myFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
myFrame.setSize(Toolkit.getDefaultToolkit().getScreenSize().width,Toolkit.getDefaultToolkit().getScreenSize().height);
myFrame.setVisible(true);
}

public void paint(Graphics g)
{
g.drawImage(screenImage,0,0,this);
}

public static void main(String[]args)
{
CaptureScreen cs=new CaptureScreen();
}
}

*************************************************************
JUST COMPILE AND EXECUTE IT
*************************************************************

Change default metal look and feel color

2009-03-06T01:51:00.003+08:00

*********************************************************************
COMPLETE SOURCE CODE FOR : ChangeMetalLookAndFeelColor.java
*********************************************************************


import javax.swing.plaf.metal.DefaultMetalTheme;

import javax.swing.plaf.metal.MetalLookAndFeel;

import javax.swing.plaf.ColorUIResource;

import javax.swing.*;

import java.awt.FlowLayout;

public class ChangeMetalLookAndFeelColor
{
public ChangeMetalLookAndFeelColor()
{
 JFrame.setDefaultLookAndFeelDecorated(true);

 MetalLookAndFeel.setCurrentTheme(new OrangeTheme());

 JFrame frame=new JFrame("Orange Theme");

 frame.getContentPane().setLayout(new FlowLayout());

 frame.getContentPane().add(new JButton("JButton"));
 frame.getContentPane().add(new JCheckBox("JCheckBox"));
 frame.getContentPane().add(new JTextField("JTextField"));

 frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 frame.setSize(500,500);
 frame.setLocationRelativeTo(null);
 frame.setVisible(true);
}

public static void main(String[]args)
{
 ChangeMetalLookAndFeelColor cmlafm=new ChangeMetalLookAndFeelColor();
}

class OrangeTheme extends DefaultMetalTheme
{
 //NEW COLOR FOR METAL LOOK AND FEEL
 ColorUIResource primary1=new ColorUIResource(255,215,76);
 ColorUIResource primary2=new ColorUIResource(255,198,0);
 ColorUIResource primary3=new ColorUIResource(205,162,11);

 ColorUIResource secondary1=new ColorUIResource(255,187,57);
 ColorUIResource secondary2=new ColorUIResource(255,168,0);
 ColorUIResource secondary3=new ColorUIResource(255,214,104);
 //NEW COLOR FOR METAL LOOK AND FEEL

 protected ColorUIResource getPrimary1()
 {
  return primary1;
 }

 protected ColorUIResource getPrimary2()
 {
  return primary2;
 }

 protected ColorUIResource getPrimary3()
 {
  return primary3;
 }

 protected ColorUIResource getSecondary1()
 {
  return secondary1;
 }

 protected ColorUIResource getSecondary2()
 {
  return secondary2;
 }

 protected ColorUIResource getSecondary3()
 {
  return secondary3;
 }
}
}

*********************************************************************
JUST COMPILE AND EXECUTE IT
*********************************************************************

Get last selected JRadioButton

2009-03-03T02:03:00.003+08:00

Complete source code below will show you, how to get last selected JRadioButton when we click on other JRadioButton. I hope you will understand what i want to tell you, or you can try to compile and execute source code below.

******************************************************************
COMPLETE SOURCE CODE FOR : GetLastSelectedJRadioButton.java
******************************************************************


import javax.swing.*;

import java.awt.*;

import java.awt.event.*;

public class GetLastSelectedJRadioButton implements ItemListener
{
JRadioButton jrd1=new JRadioButton("a");
JRadioButton jrd2=new JRadioButton("b");
JRadioButton jrd3=new JRadioButton("c");
JRadioButton jrd4=new JRadioButton("d");

JRadioButton last=null;

ButtonGroup bg=new ButtonGroup();

JFrame myFrame=new JFrame("Get last selected JRadioButton");

public GetLastSelectedJRadioButton()
{
 jrd1.addItemListener(this);
 jrd2.addItemListener(this);
 jrd3.addItemListener(this);
 jrd4.addItemListener(this);

 bg.add(jrd1);
 bg.add(jrd2);
 bg.add(jrd3);
 bg.add(jrd4);

 myFrame.getContentPane().setLayout(new GridLayout(4,1));

 myFrame.getContentPane().add(jrd1);
 myFrame.getContentPane().add(jrd2);
 myFrame.getContentPane().add(jrd3);
 myFrame.getContentPane().add(jrd4);

 myFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 myFrame.setSize(400,400);
 myFrame.setLocationRelativeTo(null);
 myFrame.setVisible(true);
}

public void itemStateChanged(ItemEvent event)
{
 JRadioButton temp=(JRadioButton)event.getItem();

 if(event.getStateChange()==ItemEvent.DESELECTED)
 {
  last=temp;
 }
 else if(event.getStateChange()==ItemEvent.SELECTED)
 {
  if(last!=null)
  {
   JOptionPane.showMessageDialog(myFrame,"LAST : "+last.getText(),"Last",JOptionPane.INFORMATION_MESSAGE);
  }
 }
}

public static void main(String[]args)
{
 GetLastSelectedJRadioButton glsjrb=new GetLastSelectedJRadioButton();
}
}

******************************************************************
JUST COMPILE AND EXECUTE IT
******************************************************************

Set JFrame decoration to MetalLookAndFeel decoration

2009-03-02T22:57:00.004+08:00

************************************************************************
COMPLETE SOURCE CODE FOR : SetJFrameDecorationToMetalLookAndFeel.java
************************************************************************


import javax.swing.*;
import java.awt.FlowLayout;

public class SetJFrameDecorationToMetalLookAndFeel
{
public static void main(String[]args)
{
 //Set JFrame decoration to current look and feel decoration
 //You can try to make this line as comment and
 //after that try compile and execute it to see it's differential
       JFrame.setDefaultLookAndFeelDecorated(true);
      
       JButton myButton=new JButton("Click On Me");
      
 JFrame myFrame=new JFrame("Set JFrame window decoration to current look and feel");
 myFrame.setLayout(new FlowLayout());

 myFrame.add(myButton);
 myFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 myFrame.setSize(400,400);
 myFrame.setLocationRelativeTo(null);
 myFrame.setVisible(true);
}
}

************************************************************************
JUST COMPILE AND EXECUTE IT
************************************************************************

Check word in String

2009-03-01T22:26:00.003+08:00

Complete source code below will show you how to check word if exist or not in a String. It will compare a word that we want to check with all word that separate by white space in targeted String. Comparison will ignore case.

**************************************************************
COMPLETE SOURCE CODE FOR : CheckWordInString.java
**************************************************************


import java.util.StringTokenizer;

public class CheckWordInString
{
public static void main(String[]args)
{
 String a="Hello World !";

 /*
  *Word(hello) that we want
  *to check if exist
  *or not in String a
  */
 String b="hello";

 /*
  *Get all word that
  *separate by white space
  *in String a
  */
 StringTokenizer st
  =new StringTokenizer(a);
  
 while(st.hasMoreTokens())
 {
  String temp=st.nextToken();
 
  /*
   *Compare with
   *ignore case
   */
  if(temp.equalsIgnoreCase(b))
  {
   System.out.println
    ("b exist in a");
   break;
  }
 }
}
}

**************************************************************
JUST COMPILE AND EXECUTE IT
**************************************************************

Java simple timer

2009-02-28T01:51:00.004+08:00

Complete source code below will show you, how to create simple timer using java. Actually it has a problem. The problem that i mean is, it seem more slow than real timer.If you find how to solve it, i hope you can share with me by put a comment.

*******************************************************************
COMPLETE SOURCE CODE FOR : JavaSimpleTimer.java
*******************************************************************


import javax.swing.*;

import java.awt.event.*;

import java.awt.*;

public class JavaSimpleTimer extends JPanel implements ActionListener
{
int miliseconds=0;
int seconds=0;
int minutes=0;

Timer myTimer;

Font timerFont=new Font("Verdana",Font.BOLD,24);

public JavaSimpleTimer()
{
myTimer=new Timer(10,this);

JFrame myFrame=new JFrame("Simple Timer");

myFrame.add(this);
myFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
myFrame.setSize(500,500);
myFrame.setVisible(true);

myTimer.setInitialDelay(0);
myTimer.start();
}

public void paint(Graphics g)
{
super.paint(g);
String mili=Integer.toString(miliseconds);
String sec=Integer.toString(seconds);
String min=Integer.toString(minutes);

if(mili.length()==1)
{
 mili="0"+mili;
}
if(sec.length()==1)
{
 sec="0"+sec;
}
if(min.length()==1)
{
 min="0"+min;
}

g.setFont(timerFont);

g.drawString(min+" :",20,20);
g.drawString(sec+" :",80,20);
g.drawString(mili,140,20);
}

public void actionPerformed(ActionEvent event)
{
miliseconds=miliseconds+1;
if(miliseconds==100)
{
 miliseconds=0;
 seconds=seconds+1;
}
if(seconds==60)
{
 seconds=0;
 minutes=minutes+1;
}
repaint();
}

public static void main(String[]args)
{
JavaSimpleTimer myTest=new JavaSimpleTimer();
}
}

*******************************************************************
JUST COMPILE AND EXECUTE IT
*******************************************************************

Set JSlider tick color

2009-02-25T16:13:00.003+08:00

Complete source code below will show you, how to set JSlider tick color. I have tried to find method in JSlider class to set JSlider tick color...but, i can't find it. So i tried to create UI Delegate only for SliderUI that change JSlider tick color. You can try to compile both source code below. Make sure both java file below locate at the same location. JSlider's tick color is set in MyNewMetalSliderUI.java.You can try to change it's color follow what color that you want base on RGB value. After you compile SetJSliderTickColor.java and MyNewMetalSliderUI.java, you try execute SetJSliderTickColor.java. This is because, main method contain in this file.Oooo...before i forget, it's only handle horizontal slider. If you want to make it can use for vertical slider, you can try overwrite method paintMajorTickForVertSlider(Graphics g, Rectangle tickBounds, int y) and paintMinorTickForVertSlider(Graphics g, Rectangle tickBounds, int y) in MetalSliderUI class. You can review it in Java SE API for MetalSliderUI class.

**********************************************************************
COMPLETE SOURCE CODE FOR : MyNewMetalSliderUI.java
**********************************************************************


import javax.swing.*;

import java.awt.*;

import javax.swing.plaf.ColorUIResource;

import javax.swing.plaf.metal.MetalSliderUI;

import javax.swing.plaf.ComponentUI;

public class MyNewMetalSliderUI extends MetalSliderUI
{
// Create our own slider UI
public static ComponentUI createUI(JComponent c )
{
 return new MyNewMetalSliderUI();
}

//*******************HORIZONTAL MAJOR TICK*******************
public void paintMajorTickForHorizSlider(Graphics g, Rectangle tickBounds, int x)
{
 int coordinateX=x;

 if(slider.getOrientation()==JSlider.HORIZONTAL)
 {
  //Create color using RGB value(RED=255,GREEN=0,BLUE=0)
  //You can use Color picker above to get RGB value for color that you want
  Color majorTickColor=new Color(255,0,0);
 
  //Set color that will use to draw MAJOR TICK using created color
  g.setColor(majorTickColor);
 
  //Draw MAJOR TICK
  g.drawLine(coordinateX,0,coordinateX,tickBounds.height);
 }
}
//*******************HORIZONTAL MAJOR TICK*******************

//*******************HORIZONTAL MINOR TICK*******************
public void paintMinorTickForHorizSlider(Graphics g, Rectangle tickBounds, int x)
{
 int coordinateX=x;

 if(slider.getOrientation()==JSlider.HORIZONTAL)
 {
  //Create color using RGB value(RED=12,GREEN=255,BLUE=0)
  //You can use Color picker above to get RGB value for color that you want
  Color majorTickColor=new Color(12,255,0);
 
  //Set color that will use to draw MINOR TICK using created color
  g.setColor(majorTickColor);
 
  //Draw MINOR TICK
  g.drawLine(coordinateX,0,coordinateX,tickBounds.height/2);
 }
}
//*******************HORIZONTAL MINOR TICK*******************
}

**********************************************************************
JUST COMPILE
**********************************************************************

**********************************************************************
COMPLETE SOURCE CODE FOR : SetJSliderTickColor.java
**********************************************************************


import javax.swing.*;

import java.awt.*;

public class SetJSliderTickColor
{
public SetJSliderTickColor()
{
 //Create slider using JSlider
 JSlider mySlider=new JSlider();

 //Set major tick spacing to 10
 mySlider.setMajorTickSpacing(10);

 //Set minor tick spacing to 1
 mySlider.setMinorTickSpacing(1);

 //Make slider's numbers visible
 mySlider.setPaintLabels(true);

 //Make slider's ticks visible
 mySlider.setPaintTicks(true);

 //Create a window using JFrame with title ( Set JSlider tick color )
 JFrame frame=new JFrame("Set JSlider tick color");

 //Set JFrame layout to FlowLayout
 frame.setLayout(new FlowLayout());

 //Add created JSlider into JFrame
 frame.add(mySlider);

 //Set JFrame's default close operation
 frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

 //Set JFrame size
 frame.setSize(500,300);

 //Set JFrame locate at center of screen
 frame.setLocationRelativeTo(null);

 //Make JFrame visible
 frame.setVisible(true);
}

public static void main(String[]args)
{
 /***********Set our own UI Delegate for Slider*************/
 UIManager uim=new UIManager();

 //MyNewMetalSliderUI contain settings that use to change tick color
 uim.put("SliderUI","MyNewMetalSliderUI");
 /***********Set our own UI Delegate for Slider*************/

 SetJSliderTickColor sjstc=new SetJSliderTickColor();
}
}

**********************************************************************
JUST COMPILE AND EXECUTE
**********************************************************************

Set JOptionPane warning icon

2009-02-20T07:53:00.002+08:00

Complete source code below will show you, how to set warning icon in JOptionPane.

**************************************************************************
COMPLETE SOURCE CODE FOR : SetJOptionPaneWarningIcon.java
**************************************************************************


import javax.swing.*;

public class SetJOptionPaneWarningIcon
{
public static void main(String[]args)
{
 //null-Message Box appear in no parent component
 //Warning Icon-text in message box
 //WARNING-JOptionPane title
 //JOptionPane.WARNING_MESSAGE-Set warning icon that will be show in message box
 JOptionPane.showMessageDialog(null,"Warning Icon","WARNING",JOptionPane.WARNING_MESSAGE);
}
}

**************************************************************************
JUST COMPILE AND EXECUTE IT
**************************************************************************

Set JOptionPane error icon

2009-02-20T07:47:00.002+08:00

Complete source code below will show you, how to set error icon in JOptionPane.

**************************************************************************
COMPLETE SOURCE CODE FOR : SetJOptionPaneErrorIcon.java
**************************************************************************


import javax.swing.*;

public class SetJOptionPaneErrorIcon
{
public static void main(String[]args)
{
 //null-Message Box appear in no parent component
 //Error Icon-text in message box
 //ERROR-JOptionPane title
 //JOptionPane.ERROR_MESSAGE-Set error icon that will be show in message box
 JOptionPane.showMessageDialog(null,"Error Icon","ERROR",JOptionPane.ERROR_MESSAGE);
}
}

**************************************************************************
JUST COMPILE AND EXECUTE IT
**************************************************************************

Set JOptionPane information icon

2009-02-20T07:36:00.003+08:00

Complete source code below will show you, how to set information icon in JOptionPane.

**************************************************************************
COMPLETE SOURCE CODE FOR : SetJOptionPaneInformationIcon.java
**************************************************************************


import javax.swing.*;

public class SetJOptionPaneInformationIcon
{
public static void main(String[]args)
{
 //null-Message Box appear in no parent component
 //Information Icon-text in message box
 //INFORMATION-JOptionPane title
 //JOptionPane.INFORMATION_MESSAGE-Set information icon that will be show in message box
 JOptionPane.showMessageDialog(null,"Information Icon","INFORMATION",JOptionPane.INFORMATION_MESSAGE);
}
}

**************************************************************************
JUST COMPILE AND EXECUTE IT
**************************************************************************

Set JOptionPane question icon

2009-02-20T07:31:00.003+08:00

Complete source code below will show you, how to set question icon in JOptionPane.

**************************************************************************
COMPLETE SOURCE CODE FOR : SetJOptionPaneQuestionIcon.java
**************************************************************************


import javax.swing.*;

public class SetJOptionPaneQuestionIcon
{
public static void main(String[]args)
{
 //null-Message Box appear in no parent component
 //Question Icon-text in message box
 //QUESTION-JOptionPane title
 //JOptionPane.QUESTION_MESSAGE-Set question icon that will be show in message box
 JOptionPane.showMessageDialog(null,"Question Icon","QUESTION",JOptionPane.QUESTION_MESSAGE);
}
}

**************************************************************************
JUST COMPILE AND EXECUTE IT
**************************************************************************

Create simple digital clock in java

2009-02-20T02:17:00.004+08:00

Complete source code below, will show you, how to create simple digital clock in java.

************************************************************************
COMPLETE SOURCE CODE FOR : SimpleDigitalClock.java
************************************************************************


import javax.swing.*;

import java.awt.*;

import java.util.Date;

public class SimpleDigitalClock extends JPanel
{
JFrame frame;

int currentHour;
int currentMinute;
int currentSecond;

//Font that will be use to show digital clock
Font myFont=new Font("Tahoma",Font.BOLD+Font.ITALIC,20);

//Color that will be use to show digital clock
Color myColor=new Color(255,0,0);

//Font metrics that will use to store font informations
//For example, width of a character
FontMetrics fm;

public SimpleDigitalClock()
{
//Create a window using JFrame with title ( Simple Digital Clock )
frame=new JFrame("Simple Digital Clock");

//add(this) mean add created panel into JFrame
//Which panel ?
//See line 81 and 7 (I hope you understand it)
frame.add(this);

//Set default close operation for JFrame
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

//Set JFrame size
frame.setSize(300,300);

//Make JFrame locate at center
frame.setLocationRelativeTo(null);

//Make JFrame visible
frame.setVisible(true);

/*
 *Loop that will make sure panel show current time
 *like current second, current minute and current hour.
 */
while(true)
{
 //It will do all code in method paint(See line 67)
 repaint();

 try
 {
  Thread.sleep(900);
 }
 catch(Exception exception)
 {
  exception.printStackTrace();
 }
}
}

public void paint(Graphics g)
{
super.paint(g);

/*
 *Create  current Date object. It means it store information
 *about current hour, minute and second.
 */
Date myDate=new Date();

currentHour=myDate.getHours();
currentMinute=myDate.getMinutes();
currentSecond=myDate.getSeconds();

//Set font that will use to draw digital number
g.setFont(myFont);

//Information about distance between number in digital clock
fm=g.getFontMetrics();
int hourXCoordinate=20;
int minuteXCoordinate=hourXCoordinate+(fm.getMaxAdvance()*2);
int secondXCoordinate=hourXCoordinate+(fm.getMaxAdvance()*4);

//Set color that will use to draw digital number
g.setColor(myColor);

//Draw hour, draw (:) between number, draw minute and draw second.
g.drawString(Integer.toString(currentHour),hourXCoordinate,20);
g.drawString(":",(hourXCoordinate+minuteXCoordinate)/2,20);
g.drawString(Integer.toString(currentMinute),minuteXCoordinate,20);
g.drawString(":",(secondXCoordinate+minuteXCoordinate)/2,20);
g.drawString(Integer.toString(currentSecond),secondXCoordinate,20);
}

public static void main(String[]args)
{
SimpleDigitalClock sdc=new SimpleDigitalClock();
}
}

************************************************************************
JUST COMPILE AND EXECUTE IT
************************************************************************

Get current second

2009-02-19T22:25:00.004+08:00

Complete source code below, will show you how to get current computer second and print the value. The second value that it get is second value at program executing time.

>>Get current minute
>>Get current hour
>>Get current computer time in java

******************************************************************
COMPLETE SOURCE CODE FOR : GetCurrentSecond.java
******************************************************************


import java.util.Date;

public class GetCurrentSecond
{
public static void main(String[]args)
{
Date myDate=new Date();

//Get current second
int currentSecond=myDate.getSeconds();

//Print current second that we get
System.out.println("Current second is : "+currentSecond);
}
}

******************************************************************
JUST COMPILE AND EXECUTE IT
******************************************************************

Get current minute

2009-02-19T21:50:00.004+08:00

Complete source code below will print current computer minute.

>>Get current second
>>Get current hour
>>Get current computer time in java

*******************************************************************
COMPLETE SOURCE CODE FOR : GetCurrentMinute.java
*******************************************************************


import java.util.Date;

public class GetCurrentMinute
{
public static void main(String[]args)
{
 Date myDate=new Date();

 //Get current minute
 int currentMinute=myDate.getMinutes();

 //Print current minute that we get
 System.out.println("Current minute is : "+currentMinute);
}
}

*******************************************************************
JUST COMPILE AND EXECUTE IT
*******************************************************************

Get current hour

2009-02-19T21:25:00.004+08:00

Complete source code below will print current computer hour in soldier time format.Soldier time format is 24 hour format.

>>Get current minute
>>Get current second
>>Get current computer time in java

**************************************************************
COMPLETE SOURCE CODE FOR : GetCurrentHour.java
**************************************************************


import java.util.Date;

public class GetCurrentHour
{
public static void main(String[]args)
{
 Date myDate=new Date();

 //Get current hour in soldier time format
 int currentHour=myDate.getHours();

 //Print current hour that we get
 System.out.println("Current hour is : "+currentHour);
}
}

**************************************************************
JUST COMPILE AND EXECUTE IT
**************************************************************

Get current computer time in java

2009-02-19T21:15:00.004+08:00

Complete source code below will show you, how to get current computer time in java.

*******************************************************************
COMPLETE SOURCE CODE FOR : GetCurrentTime.java
*******************************************************************


import java.util.Date;

public class GetCurrentTime
{
public static void main(String[]args)
{
Date myDate=new Date();

System.out.println(myDate.getHours()+":"+myDate.getMinutes()+":"+myDate.getSeconds());
}
}

*******************************************************************
JUST COMPILE AND EXECUTE IT
*******************************************************************

Set ToolTipText background color

2009-02-17T17:25:00.003+08:00

Complete source code below, will show you how to set ToolTipText background color.

**************************************************************************
COMPLETE SOURCE CODE FOR : SetToolTipTextBackgroundColor.java
**************************************************************************


import javax.swing.UIManager;
import javax.swing.JFrame;
import javax.swing.JButton;

import java.awt.FlowLayout;
import java.awt.Color;

public class SetToolTipTextBackgroundColor
{
/**
 *Create a button with text ( Put your cursor on me )
 */
JButton button=new JButton("Put your cursor on me");

//Create a window using JFrame with text ( Set ToolTipText background color )
JFrame frame=new JFrame("Set ToolTipText background color");

public SetToolTipTextBackgroundColor()
{
 //Create a color base on RGB value
 //You can get your color value base on RGB using Color picker at above
 //R=204 G=0 B=153
 Color backgroundColor=new Color(204,0,153);

 //Create UIManager
 UIManager uim=new UIManager();

 //Set tooltiptext background color using created Color
 uim.put("ToolTip.background",backgroundColor);

 //Set tooltiptext for created button
 button.setToolTipText("I am a button");

 frame.setLayout(new FlowLayout());
 frame.add(button);
 frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 frame.setSize(400,400);
 frame.setLocationRelativeTo(null);
 frame.setVisible(true);
}

public static void main(String[]args)
{
 SetToolTipTextBackgroundColor stttbc=new SetToolTipTextBackgroundColor();
}
}

**************************************************************************
JUST COMPILE AND EXECUTE IT
**************************************************************************

Set ToolTipText text font

2009-02-17T17:13:00.002+08:00

Complete source code below, will show you how to set ToolTipText text font.

************************************************************************
COMPLETE SOURCE CODE FOR : SetToolTipTextFont.java
************************************************************************


import javax.swing.UIManager;
import javax.swing.JFrame;
import javax.swing.JButton;

import java.awt.FlowLayout;
import java.awt.Font;

public class SetToolTipTextFont
{
/**
 *Create a button with text ( Put your cursor on me )
 */
JButton button=new JButton("Put your cursor on me");

//Create a window using JFrame with text ( Set ToolTipText text font )
JFrame frame=new JFrame("Set ToolTipText text font");

public SetToolTipTextFont()
{
 //Create a font :
 //Name : Verdana
 //Style : Bold
 //Size : 20
 Font textFont=new Font("Verdana",Font.BOLD,20);

 //Create UIManager
 UIManager uim=new UIManager();

 //Set tooltiptext text font using created Font
 uim.put("ToolTip.font",textFont);

 //Set tooltiptext for created button
 button.setToolTipText("I am a button");

 frame.setLayout(new FlowLayout());
 frame.add(button);
 frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 frame.setSize(400,400);
 frame.setLocationRelativeTo(null);
 frame.setVisible(true);
}

public static void main(String[]args)
{
 SetToolTipTextFont stttf=new SetToolTipTextFont();
}
}

************************************************************************
JUST COMPILE AND EXECUTE IT
************************************************************************

Set ToolTipText text color

2009-02-17T15:43:00.004+08:00

Complete source code below, will show you how to set ToolTipText text color.

************************************************************************
COMPLETE SOURCE CODE FOR : SetToolTipTextColor.java
************************************************************************


import javax.swing.UIManager;
import javax.swing.JFrame;
import javax.swing.JButton;

import java.awt.FlowLayout;
import java.awt.Color;

public class SetToolTipTextColor
{
/**
 *Create a button with text ( Put your cursor on me )
 */
JButton button=new JButton("Put your cursor on me");

//Create a window using JFrame with title ( Set ToolTipText text color )
JFrame frame=new JFrame("Set ToolTipText text color");

public SetToolTipTextColor()
{
 //Create a color base on RGB value
 //You can get your color value base on RGB using Color picker at above
 //R=255 G=255 B=255 is RGB value for white
 Color textColor=new Color(255,255,255);

 //Create UIManager
 UIManager uim=new UIManager();

 //Set tooltiptext text color using created Color
 uim.put("ToolTip.foreground",textColor);

 //Set tooltiptext for created button
 //So, it's tooltiptext text color will be WHITE
 button.setToolTipText("I am a button");

 frame.setLayout(new FlowLayout());
 frame.add(button);
 frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 frame.setSize(400,400);
 frame.setLocationRelativeTo(null);
 frame.setVisible(true);
}

public static void main(String[]args)
{
 SetToolTipTextColor stttc=new SetToolTipTextColor();
}
}

************************************************************************
JUST COMPILE AND EXECUTE IT
************************************************************************

Set JOptionPane icons

2009-02-16T08:52:00.006+08:00

Complete source code below will show you, how to set JOptionPane icons using any GIF image. Before you compile and execute complete source code below, you need to download all images below and place them with your java file that contain source code below.You also can use any GIF image that you want, but make sure it's location is right. This is because i suggest you place all GIF image at same location with source code file. So you don't need to put any file path in your source code. If you still want to use GIF image at other location, you can try step by step below.

For example, your GIF image with name MyImage.gif locate at C:\Documents and Settings...like below :

C:\Documents and Settings\MyImage.gif

So, you must put in your source code like this :
"C:\\Documents and Settings\\MyImage.gif"

WARNING.gif

QUESTION.gif

INFORMATION.gif

ERROR.gif

Click here for how to create all icons above

****************************************************************
COMPLETE SOURCE CODE FOR : ChangeJOptionPaneIcons.java
****************************************************************


import javax.swing.JFrame;
import javax.swing.JButton;
import javax.swing.JOptionPane;
import javax.swing.UIManager;
import javax.swing.LookAndFeel;

import java.awt.GridLayout;

import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;

public class ChangeJOptionPaneIcons implements ActionListener
{

JButton button=new JButton("JOptionPane with Error Icon");
JButton button2=new JButton("JOptionPane with Information Icon");
JButton button3=new JButton("JOptionPane with Question Icon");
JButton button4=new JButton("JOptionPane with Warning Icon");

JFrame frame=new JFrame("Change JOptionPane icons");

public ChangeJOptionPaneIcons()
{
 //---START SETTING NEW ICON---
 UIManager uim=new UIManager();

 Object error=LookAndFeel.makeIcon(getClass(),"ERROR.gif");
 Object information=LookAndFeel.makeIcon(getClass(),"INFORMATION.gif");
 Object question=LookAndFeel.makeIcon(getClass(),"QUESTION.gif");
 Object warning=LookAndFeel.makeIcon(getClass(),"WARNING.gif");

 //Set new icon for Error message
 uim.put("OptionPane.errorIcon",error);

 //Set new icon for Information message
 uim.put("OptionPane.informationIcon",information);

 //Set new icon for Question message
 uim.put("OptionPane.questionIcon",question);

 //Set new icon for Warning message
 uim.put("OptionPane.warningIcon",warning);
 //---END SETTING NEW ICON---

 button.addActionListener(this);
 button2.addActionListener(this);
 button3.addActionListener(this);
 button4.addActionListener(this);

 frame.setLayout(new GridLayout(4,1));
 frame.add(button);
 frame.add(button2);
 frame.add(button3);
 frame.add(button4);

 frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 frame.setSize(400,200);
 frame.setLocationRelativeTo(null);
 frame.setVisible(true);
}

public void actionPerformed(ActionEvent event)
{
 if(event.getSource()==button)
 {
  JOptionPane.showMessageDialog(frame,"Error Icon","ERROR",JOptionPane.ERROR_MESSAGE);
 }
 else if(event.getSource()==button2)
 {
  JOptionPane.showMessageDialog(frame,"Information Icon","INFORMATION",JOptionPane.INFORMATION_MESSAGE);
 }
 else if(event.getSource()==button3)
 {
  JOptionPane.showMessageDialog(frame,"Question Icon","QUESTION",JOptionPane.QUESTION_MESSAGE);
 }
 else if(event.getSource()==button4)
 {
  JOptionPane.showMessageDialog(frame,"Warning Icon","WARNING",JOptionPane.WARNING_MESSAGE);
 }
}

public static void main(String[]args)
{
 ChangeJOptionPaneIcons cjopi=new ChangeJOptionPaneIcons();
}
}
//END

****************************************************************
JUST COMPILE AND EXECUTE IT
****************************************************************

Get date using Calendar class

2009-02-13T00:22:00.007+08:00

Complete source code below will show you, how to get date on local computer in java using Calendar class.



import java.util.Calendar;
import java.util.Locale;

public class GetDate
{
public static void main(String[]args)
{
 //Get a calendar using the default time zone and locale.
 Calendar currentComputerDate=Calendar.getInstance();

 //Print date
 System.out.print(currentComputerDate.get(Calendar.DATE));
 System.out.print(".");

 /*Print month in text representation. For example January is first month.
  *Month that will print is in long representation.
  *Short representation for January is Jan
  *You can try to change Calendar.LONG to Calendar.SHORT
  *Local.ROOT is useful constant for the root locale.
  */
    System.out.print(currentComputerDate.getDisplayName(Calendar.MONTH,Calendar.LONG,Locale.ROOT));
 System.out.print(".");

 //Print year
 System.out.print(currentComputerDate.get(Calendar.YEAR));
}
}

Get selected JRadioButton from ButtonGroup

2009-02-08T02:26:00.005+08:00

Complete source code below will show you, how to get selected JRadioButton from ButtonGroup.

*************************************************************************
COMPLETE SOURCE CODE FOR : GetSelectedJRadioButtonFromButtonGroup.java
*************************************************************************


import javax.swing.JRadioButton;
import javax.swing.ButtonGroup;
import javax.swing.JFrame;
import javax.swing.JButton;
import javax.swing.JPanel;
import javax.swing.JOptionPane;
import javax.swing.AbstractButton;

import java.awt.BorderLayout;

import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;

import java.util.Enumeration;

public class GetSelectedJRadioButtonFromButtonGroup implements ActionListener
{
//Create two radio button that will be put into a group
//Set start radio button selection to female
JRadioButton firstRadioButton=new JRadioButton("Female",true);
JRadioButton secondRadioButton=new JRadioButton("Male");

//Create a button with text ( What i select )
JButton button=new JButton("What i select");

//Create a window using JFrame with title ( Get selected JRadioButton from ButtonGroup)
JFrame frame=new JFrame("Get selected JRadioButton from ButtonGroup");

//Create a radio button group using ButtonGroup
ButtonGroup bg=new ButtonGroup();

public GetSelectedJRadioButtonFromButtonGroup()
{
 //Add all radio button into created group
 bg.add(firstRadioButton);
 bg.add(secondRadioButton);

 //Set JFrame layout to border layout
 frame.setLayout(new BorderLayout());

 //Create a panel that will be put radio button into it
 JPanel panel=new JPanel();

 //Add all created radio button into panel
 panel.add(firstRadioButton);
 panel.add(secondRadioButton);

 //Add action listener to created button
 button.addActionListener(this);

 //Add panel and button into JFrame
 frame.add(panel,BorderLayout.CENTER);
 frame.add(button,BorderLayout.SOUTH);

 //Set default close operation for JFrame
 frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

 //Set JFrame size
 frame.setSize(600,150);

 //Make JFrame visible
 frame.setVisible(true);
}

   //Action for button
   //Get selected JRadioButton from ButtonGroup
public void actionPerformed(ActionEvent event)
{
 if(event.getSource()==button)
 {
  Enumeration<AbstractButton> allRadioButton=bg.getElements();
 
  while(allRadioButton.hasMoreElements())
  {
   JRadioButton temp=(JRadioButton)allRadioButton.nextElement();
   if(temp.isSelected())
   {
    JOptionPane.showMessageDialog(frame,"You select : "+temp.getText());
   }
  }
 }
}

public static void main(String[]args)
{
 GetSelectedJRadioButtonFromButtonGroup gsjrbfbg=new  GetSelectedJRadioButtonFromButtonGroup();
}
}

*************************************************************************
JUST COMPILE AND EXECUTE IT
*************************************************************************

Two text field in JOptionPane

2009-02-07T16:39:00.005+08:00

Complete source code below will show you, how to put two text field into JOptionPane. First text field is to receive username from user and second is to receive password from user. This gui is suitable when you want to receive username and password from user using JOptionPane.

username : jamesBond
password : 007

***********************************************************************
COMPLETE SOURCE CODE FOR : TwoTextFieldInJOptionPane.java
***********************************************************************


import javax.swing.*;

import java.awt.*;

public class TwoTextFieldInJOptionPane
{
public static void main(String[]args)
{
 //Create a panel that will be use to put
 //one JTextField, one JPasswordField and two JLabel
 JPanel panel=new JPanel();

 //Set JPanel layout using GridLayout
 panel.setLayout(new GridLayout(4,1));

 //Create a label with text (Username)
 JLabel username=new JLabel("Username");

 //Create a label with text (Password)
 JLabel password=new JLabel("Password");

 //Create text field that will use to enter username
 JTextField textField=new JTextField(12);

 //Create password field that will be use to enter password
 JPasswordField passwordField=new JPasswordField(12);

 //Add label with text (username) into created panel
 panel.add(username);

 //Add text field into created panel
 panel.add(textField);

 //Add label with text (password) into created panel
 panel.add(password);

 //Add password field into created panel
 panel.add(passwordField);

 //Create a window using JFrame with title ( Two text component in JOptionPane )
 JFrame frame=new JFrame("Two text component in JOptionPane");

 //Set default close operation for JFrame
 frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

 //Set JFrame size
 frame.setSize(300,300);

 //Set JFrame locate at center
 frame.setLocationRelativeTo(null);

 //Make JFrame visible
 frame.setVisible(true);

 //Show JOptionPane that will ask user for username and password
 int a=JOptionPane.showConfirmDialog(frame,panel,"Put username and password",JOptionPane.OK_CANCEL_OPTION,JOptionPane.QUESTION_MESSAGE);

 //Operation that will do when user click 'OK'
 if(a==JOptionPane.OK_OPTION)
 {
  if(textField.getText().equals("jamesBond")&&new String(passwordField.getPassword()).equals("007"))
  {
   JOptionPane.showMessageDialog(frame,"You are James Bond","Correct",JOptionPane.INFORMATION_MESSAGE);
  }
  else
  {
   JOptionPane.showMessageDialog(frame,"You are not James Bond","False",JOptionPane.ERROR_MESSAGE);
  }
 }

 //Operation that will do when user click 'Cancel'
 else if(a==JOptionPane.CANCEL_OPTION)
 {
  JOptionPane.showMessageDialog(frame,"You pressed Cancel button");
 }
}
}

***********************************************************************
JUST COMPILE AND EXECUTE IT
***********************************************************************

Open file using JFileChooser

2009-02-07T08:35:00.004+08:00

Complete source code below will show you, how to open file using JFileChooser.

*********************************************************************
COMPLETE SOURCE CODE FOR : OpenFileUsingJFileChooser.java
*********************************************************************


/*
*Desktop class only can get when you use JDK 6
*/
import java.awt.Desktop;

import javax.swing.JFileChooser;

import java.io.File;

public class OpenFileUsingJFileChooser
{
public static void main(String[]args)
{
 //Create a file chooser
 JFileChooser fileChooser=new JFileChooser();

 //File chooser will appear in no windows parent
 int a=fileChooser.showOpenDialog(null);

 //Action that will take when user click open button
 if(a==JFileChooser.APPROVE_OPTION)
 {
  //Get file that want to open
  File fileToOpen=fileChooser.getSelectedFile();

  try
  {
   //Open file using suitable program on computer.
   //You don't need to tell what program to use.
   //Java will select default program that your
   //computer use to open the file.
   //In windowsXP you can see what
   //program that your computer use to open
   //a file by right click on file,
   //choose properties and see at
   //Opens with : ProgramNameToOpenTheFile
   Desktop.getDesktop().open(fileToOpen);
  }
  catch(Exception exception)
  {
   System.out.println("Problem occour when to open the file");
  }
 }
}
}

*********************************************************************
JUST COMPILE AND EXECUTE IT
*********************************************************************

Open any file or folder using Desktop class

2009-02-06T18:29:00.004+08:00

Complete source code below will show you, how to open C:\ drive using Desktop class. Desktop class is only can get when you use jdk 6.

******************************************************************
COMPLETE SOURCE CODE FOR : OpenFileUsingDesktopClass.java
******************************************************************


/*
*If you want to use Desktop class,
*you must make sure that jdk version
*that you use is 6. This facilities
*is exist in jdk 6.
*/
import java.awt.Desktop;

import java.io.File;

public class OpenFileUsingDesktopClass
{
public static void main(String[]args)
{
 try
 {
  //Open C:\ drive
  //Make sure that you change \ to \\
  //You can change to other file or folder that you want
  //Example for file that you want to open:
  //C:\Sunset.jpg
  //So, change C:\\ below to
  //C:\\Sunset.jpg
  Desktop.getDesktop().open(new File("C:\\"));
 }
 catch(Exception exception)
 {
  exception.printStackTrace();
 }
}
}

******************************************************************
JUST COMPILE AND EXECUTE IT
******************************************************************

Click here to download jdk6
Click here to download jdk6 documentation

Set JButton text color using UIManager

2009-02-06T00:23:00.004+08:00

Complete source code below will show you, how to set JButton text color using UIManager. When you set JButton text color using this style, it will make all JButton in your program will have same text color. So, if you want to set only one text color for JButton, i suggest you click here.

**********************************************************************
COMPLETE SOURCE CODE FOR : SetJButtonForegroundColorUseUiManager.java
**********************************************************************


import javax.swing.UIManager;

import javax.swing.plaf.ColorUIResource;

import javax.swing.*;

import java.awt.*;

public class SetJButtonForegroundColorUseUiManager
{
public static void main(String[]args)
{
 /*
  *Create color base on RGB color model
  *that will use as JButton foreground color.
  *Red=255
  *Green=0
  *Blue=0
  */
 Color foregroundColor=new Color(255,0,0);

 //Set JButton foreground color
 UIManager.put("Button.foreground",new ColorUIResource(foregroundColor));

 //Create a window using JFrame with title ( Set JButton foreground color using UIManager )
 JFrame frame=new JFrame("Set JButton foreground color using UIManager");

 //Create two button
 JButton button1=new JButton("Button 1");
 JButton button2=new JButton("Button 2");

 //Set JFrame layout to FlowLayout
 frame.setLayout(new FlowLayout());

 //Add created button into frame
 frame.add(button1);
 frame.add(button2);

 //Set JFrame default close operation
 frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

 //Set JFrame size
 frame.setSize(400,400);

 //Make JFrame locate at center
 frame.setLocationRelativeTo(null);

 //Make JFrame visible
 frame.setVisible(true);
}
}

**********************************************************************
JUST COMPILE AND EXECUTE IT
**********************************************************************

Open any file or folder in java

2009-02-05T16:43:00.004+08:00

Complete source code will show you, how to open any files or folders using java in windows.What you must know is :

rundll32 SHELL32.DLL,ShellExec_RunDLL File_Or_Folder_To_Open

What is rundll32.exe And Why Is It Running?

****************************************************************
COMPLETE SOURCE CODE FOR : OpenFileUsingJava.java
****************************************************************


public class OpenFileUsingJava
{
public static void main(String[]args)
{
 try
 {
  //Path for folder or file that you want to open
  //In my case i will open C:\ drive
  //So create a String like below
  //Don't forget to change \ to \\
  String a="C:\\";
 
  //Execute command
  //Command that you must know : rundll32 SHELL32.DLL,ShellExec_RunDLL File_Or_Folder_To_Open
  Runtime.getRuntime().exec("rundll32 SHELL32.DLL,ShellExec_RunDLL \""+a+"\"");
 }
 catch(Exception exception)
 {
  exception.printStackTrace();
 }
}
}

****************************************************************
JUST COMPILE AND EXECUTE IT
****************************************************************

What is different between i++ and ++i

2009-02-05T14:48:00.003+08:00

I want to share with you about different between i++ and ++i.

++i
**********
int i=0;
System.out.println(++i);
**********
It will print on screen 1

i++
**********
int i=0;
System.out.println(i++);
**********
It will print on screen 0

Answer :
++i will add current i value with 1 before print

i++ will add current i value with 1 after print

Draw triangle in JPanel

2009-02-03T13:58:00.006+08:00

Complete source code below will show you, how to draw triangle in JPanel

*********************************************************************
COMPLETE SOURCE CODE FOR : DrawTriangle.java
*********************************************************************


import javax.swing.*;

import java.awt.*;

public class DrawTriangle extends JPanel
{
public DrawTriangle()
{
 JFrame frame=new JFrame("Draw triangle in JPanel");
 frame.add(this);

 frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 frame.setSize(400,400);
 frame.setLocationRelativeTo(null);
 frame.setVisible(true);
}

public void paint(Graphics g)
{
 super.paint(g);

 //All triangle corner x coordinate
 int[]x={0,150,300};

 //All triangle corner y coordinate
 int[]y={200,0,200};

 //Set color base on RGB
 //You can get RGB value for your color at "Color picker" at above
 //R=255
 //G=192
 //B=0
 //So after this all you draw will use this color
 g.setColor(new Color(255,192,0));

 //Draw triangle in JPanel
 g.fillPolygon(x,y,3);

 //Set color base on RGB
 //You can get RGB value for your color at "Color picker" at above
 //R=1
 //G=1
 //B=1
 //So after this all you draw will use this color
 g.setColor(new Color(1,1,1));

 //Set font that will use when draw String
 g.setFont(new Font("Arial",Font.BOLD,14));

 //Draw String in JPanel
 g.drawString("(0,200)",10,200);
 g.drawString("(150,0)",150,20);
 g.drawString("(300,200)",290,200);
}

public static void main(String[]args)
{
 DrawTriangle dt=new DrawTriangle();
}

}

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*********************************************************************

Compare current date with user input date in java

2009-02-03T07:14:00.005+08:00

Complete source code below will show you, how to compare current date with user input date in java.

***************************************************************************
COMPLETE SOURCE CODE FOR : GetDate.java
***************************************************************************


import java.util.Date;

import javax.swing.*;

import java.awt.*;

import java.awt.event.*;

public class GetDate implements ActionListener
{
int year=0;
int month=0;
int date=0;

String [] yearContent={"2000","2001","2002","2003","2004","2005","2006","2007","2008","2009","2010","2011"};
String [] monthContent={"January","February","March","April","Mei","Jun","July","August","September","October","November","December"};
String [] dateContent={"1","2","3","4","5","6","7","8","9","10",
    "11","12","13","14","15","16","17","18","19","20",
    "21","22","23","24","25","26","27","28","29","30",
    "31"};

JComboBox yearComboBox=new JComboBox(yearContent);
JComboBox monthComboBox=new JComboBox(monthContent);
JComboBox dateComboBox=new JComboBox(dateContent);

JButton button=new JButton("Click here to compare to current date");

JFrame frame=new JFrame("Compare date with current date");

public GetDate()
{
button.addActionListener(this);

Box box=Box.createHorizontalBox();
box.add(dateComboBox);
box.add(monthComboBox);
box.add(yearComboBox);

frame.setLayout(new GridLayout(2,1));

frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(box);
frame.add(button);
frame.setSize(500,100);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}

public void actionPerformed(ActionEvent event)
{
if(event.getSource()==button)
{
 String tempDate=(String)dateComboBox.getSelectedItem();
 date=Integer.parseInt(tempDate);

 month=monthComboBox.getSelectedIndex();

 String tempYear=(String)yearComboBox.getSelectedItem();
 year=Integer.parseInt(tempYear)-1900;

 Date currentDateValue=new Date();
 Date userChooserDate=new Date(year,month,date);

 int currentYear=currentDateValue.getYear();
 int currentMonth=currentDateValue.getMonth();
 int currentDate=currentDateValue.getDate();

 if((date==currentDate)&&(month==currentMonth)&&(year==currentYear))
 {
  JOptionPane.showMessageDialog(frame,"Same date","SAME",JOptionPane.INFORMATION_MESSAGE);
 }
 else if(userChooserDate.compareTo(currentDateValue)<0)>0)
 {
  JOptionPane.showMessageDialog(frame,"Welcome to the future","FUTURE",JOptionPane.INFORMATION_MESSAGE);
 }
}
}

public static void main(String[]args)
{
GetDate gd=new GetDate();
}
}

***************************************************************************
JUST COMPILE AND EXECUTE IT
***************************************************************************

Input box in java

2009-01-28T00:57:00.005+08:00

Complete source code below will show you, how to create simple input box that will prompt some input from user. We will use predefined java class, JOptionPane to create simple input box. If you want your input box appear in a container, you can change null in source code below to target container.You can see example by click here.

*************************************************************************
COMPLETE SOURCE CODE FOR : JavaInputDialog.java
*************************************************************************


import javax.swing.JOptionPane;

public class JavaInputDialog
{
public static void main(String[]args)
{
 //Pop up an input box with text ( What is your name ? )
 String a=JOptionPane.showInputDialog(null,"What is your name ?");

 //Print into command prompt what you put into input dialog box
 System.out.println("My name is : "+a);
}
}

*************************************************************************
JUST COMPILE AND EXECUTE IT
*************************************************************************

Message box appear in JFrame

2009-01-27T23:52:00.005+08:00

Complete source code below will show you, how to make message box appear in a container.

**********************************************************************
COMPLETE SOURCE CODE FOR : MessageBoxAppearInJFrame.java
**********************************************************************


import javax.swing.JOptionPane;

import javax.swing.JFrame;

public class MessageBoxAppearInJFrame
{
public static void main(String[]args)
{
 //Create a window using JFrame with title ( Message box appear in JFrame )
 JFrame frame=new JFrame("Message box appear in JFrame");

 //Set default close operation for JFrame
 frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

 //Set JFrame size
 frame.setSize(400,400);

 //Make JFrame locate at center on screen
 frame.setLocationRelativeTo(null);

 //Make JFrame visible
 frame.setVisible(true);


 //Pop up a message box with text ( I am a message dialog ) in created JFrame
 JOptionPane.showMessageDialog(frame,"I am a message dialog");
}
}

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**********************************************************************

Create message box in java

2009-01-27T23:25:00.005+08:00

Complete source code below will show you, how to create message box in java. We will use JOptionPane class to create message box. If you want your message box appear in a container, you can change null in source code below to target container.You can see example by click here.

************************************************************************
COMPLETE SOURCE CODE FOR : JavaMessageDialog.java
************************************************************************


import javax.swing.JOptionPane;

public class JavaMessageDialog
{
public static void main(String[]args)
{
 //Pop up a message box with text ( I am a message dialog )
 JOptionPane.showMessageDialog(null,"I am a message dialog");
}
}

************************************************************************
JUST COMPILE AND EXECUTE IT
************************************************************************

Read floating point number user input in java

2009-01-26T18:05:00.004+08:00

Complete source code below, will show you how to wait and read floating point number user input in command prompt.

********************************************************************
COMPLETE SOURCE CODE FOR : ReadFloatingPointNumberUserInput.java
********************************************************************


import java.util.Scanner;

public class ReadFloatingPointNumberUserInput
{
public static void main(String[]args)
{
 try
 {
  //Create a scanner object
  //Scanner is a predefined class in java that will be use to scan text
  //System.in is mean, we will receive input from standard input stream
  Scanner readUserInput=new Scanner(System.in);

  //Print into command prompt(Put a floating point number : )
  System.out.print("Put a floating point number : ");

  //Wait and READ FLOATING POINT NUMBER from user input after user hit 'Enter'
  float myPointNumber=readUserInput.nextFloat();

  //Print what store in myPointNumber
  System.out.println("My floating point number is : "+myPointNumber);
 }
 catch(Exception exception)
 {
  //Error that will be print if user put other than floating point number
  System.out.println("Hey !!! Don't put other than floating point number");
 }
}
}

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********************************************************************

Read integer user input in java

2009-01-26T17:46:00.004+08:00

Complete source code below, will show you how to wait and read integer user input in command prompt.

**********************************************************************
COMPLETE SOURCE CODE FOR : ReadIntegerUserInput.java
**********************************************************************


import java.util.Scanner;

public class ReadIntegerUserInput
{
public static void main(String[]args)
{
 try
 {
  //Create a scanner object
  //Scanner is a predefined class in java that will be use to scan text
  //System.in is mean, we will receive input from standard input stream
  Scanner readUserInput=new Scanner(System.in);

  //Print into command prompt(What is your age ?)
  System.out.println("What is your age ?");

  //Wait and READ INTEGER INPUT from user after user hit 'Enter'
  int myAge=readUserInput.nextInt();

  //Print what store in myAge
  System.out.println("Your age is : "+myAge);
 }
 catch(Exception exception)
 {
  //Error that will be print if user put other than number include
  //point number
  System.out.println("Hey !!! Don't put other than number");
 }
}
}

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**********************************************************************

Read a word user input in java

2009-01-26T16:49:00.005+08:00

Complete source code below, will show you how to wait and read only a word from user input in command prompt.

*****************************************************************
COMPLETE SOURCE CODE FOR : ReadOneWordUserInput.java
*****************************************************************


import java.util.Scanner;

public class ReadOneWordUserInput
{
public static void main(String[]args)
{
 //Create a scanner object
 //Scanner is a predefined class in java that will be use to scan text
 //System.in is mean, we will receive input from standard input stream
 Scanner readUserInput=new Scanner(System.in);

 //Print into command prompt(What is your gender ?)
 //Print into command prompt(Female/Male)
 System.out.println("What is your gender ?\nFemale/Male");

 //Wait and READ A WORD from user input after user hit 'Enter'
 //Method next() in class scanner will read only first word in user input
 //So, second word that seperate by space will be ignore.
 String myGender=readUserInput.next();

 //Print what store in myGender
 System.out.println(myGender);
}
}

*****************************************************************
JUST COMPILE AND EXECUTE IT
*****************************************************************

Read text user input in java

2009-01-26T16:23:00.004+08:00

Complete source code below, will show you how to wait and read text user input in command prompt.

********************************************************************
COMPLETE SOURCE CODE FOR : ReadTextUserInput.java
********************************************************************


import java.util.Scanner;

public class ReadTextUserInput
{
public static void main(String[]args)
{
 //Create a scanner object
 //Scanner is a predefined class in java that will be use to scan text
 //System.in is mean, we will receive input from standard input stream
 Scanner readUserInput=new Scanner(System.in);

 //Print into command prompt(What is your name ?)
 System.out.println("What is your name ?");

 //Wait and READ TEXT INPUT from user after user hit 'Enter'
 String myName=readUserInput.nextLine();

 //Print what store in myName
 System.out.println(myName);
}
}

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JUST COMPILE AND EXECUTE IT
********************************************************************

Wait user input in java

2009-01-26T15:46:00.005+08:00

Complete source code below will show you, how to wait for user input in command prompt.
Input is a line of text.

**********************************************************************
COMPLETE SOURCE CODE FOR : WaitUserInput.java
**********************************************************************


import java.util.Scanner;

public class WaitUserInput
{
public static void main(String[]args)
{
 //Create a scanner object
 //Scanner is a predefined class in java that will be use to scan text
 //System.in is mean, we will receive input from standard input stream
 Scanner readUserInput=new Scanner(System.in);

 //Print into command prompt(What is your name ?)
 System.out.println("What is your name ?");

 //WAIT FOR USER INPUT
 //After user put it's name, he or she must press 'Enter'
 //After user press 'Enter', all the input contents will read into 'myName'
 String myName=readUserInput.nextLine();

 //Print what it store in myName
 System.out.println(myName);
}
}

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**********************************************************************

User input in java

2009-01-26T15:23:00.012+08:00

Ok, now i share with you how you can handle user input in java.

>>Receive user input from command line

Wait for user input

Read text user input in java

Read a word user input in java

Read integer input in java

Read floating point number user input in java

>>Receive user input from input box

Create simple input box in java

>>Receive user input from text field

Get JTextField text

>>Receive user input from text area

Get JTextArea text

Tip for BoxLayout

2009-01-25T23:09:00.004+08:00

BoxLayout enable we arrange components into two direction. Firstly is horizontal and secondly is vertical.

Example source code for set layout using BoxLayout

Set JPanel layout using BoxLayout

2009-01-25T23:03:00.005+08:00

Complete source code below will show you how to set JPanel layout using BoxLayout

*******************************************************************
COMPLETE SOURCE CODE FOR : SetJPanelLayoutUsingBoxLayout.java
*******************************************************************


import javax.swing.*;

import java.awt.*;

public class SetJPanelLayoutUsingBoxLayout
{
public static void main(String[]args)
{
 //Create a window using JFrame with title ( Set JPanel layout using BoxLayout )
 JFrame frame=new JFrame("Set JPanel layout using BoxLayout");

 //Create a panel using JPanel
 JPanel panel=new JPanel();

 //Set JPanel layout using BoxLayout with vertical lay out
 //You can try change to BoxLayout.X_AXIS to make components lay out in horizontal
 panel.setLayout(new BoxLayout(panel,BoxLayout.Y_AXIS));

 //Create a button with text ( First button )
 JButton button=new JButton("First button");

 //Create a button with text ( Second button )
 JButton button2=new JButton("Second button");

 //Create a button with text ( Third button )
 JButton button3=new JButton("Third button");

 //Create a dimension with :
 //Width : 10 pixels
 //Height : 10 pixels
 Dimension dim=new Dimension(10,10);

 //Create an invisible box with dimension size and add into created panel
 //You can try eliminate this and see what happen
 panel.add(Box.createRigidArea(dim));

 //Add button into panel
 panel.add(button);

 //Create an invisible box with dimension size and add into created panel
 //You can try eliminate this and see what happen
 panel.add(Box.createRigidArea(dim));

 //Add button2 into panel
 panel.add(button2);

 //Create an invisible box with dimension size and add into created panel
 //You can try eliminate this and see what happen
 panel.add(Box.createRigidArea(dim));

 //Add button3 into panel
 panel.add(button3);

 //Create an invisible box with dimension size and add into created panel
 //You can try eliminate this and see what happen
 panel.add(Box.createRigidArea(dim));

 //add panel into created JFrame
 frame.add(panel);

 //Set default close operation for JFrame
 frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

 //Set JFrame size
 frame.setSize(500,200);

 //Make JFrame locate at center of screen
 frame.setLocationRelativeTo(null);

 //Make JFrame visible
 frame.setVisible(true);
}
}

*******************************************************************
JUST COMPILE AND EXECUTE IT
*******************************************************************

Set JPanel layout using GridBagLayout

2009-01-25T20:27:00.004+08:00

Source code below will show you, how to set JPanel layout using GridBagLayout.

**************************************************************
COMPLETE SOURCE CODE FOR : SetJPanelLayoutToGridBagLayout.java
**************************************************************


import javax.swing.*;
import java.awt.*;

public class SetJPanelLayoutToGridBagLayout extends JPanel
{
/**Note**
 *When it say, "It will take 4 grid for it's width"
 *it mean it will use 4 box in grid and it's direction is to right
 *
 *When it say, "It will take 4 grid for it's height"
 *it mean it will use 4 box in grid and it's direction is to bottom
 */

//Create GridBigLayout object
GridBagLayout gbl=new GridBagLayout();

//Create GridBagConstraints object
GridBagConstraints gbc=new GridBagConstraints();

//Create a label using JLabel with text ( Name : )
JLabel label=new JLabel("Name :");

//Create a label using JLabel with text ( Age : )
JLabel label2=new JLabel("Age :");

//Create a text field using JTextField with numbers of column equal to 12
JTextField textField=new JTextField(12);

//Create a text field using JTextField with numbers of column equal to 3
JTextField textField2=new JTextField(3);

//Create a button with text ( OK )
JButton button=new JButton("OK");

//Create a button with text ( Cancel )
JButton button2=new JButton("Cancel");

//Create a box with vertical layout
Box box1=new Box(BoxLayout.Y_AXIS);

//Create a box with horizontal layout
Box box2=new Box(BoxLayout.X_AXIS);

//Create a box with horizontal layout
Box box3=new Box(BoxLayout.X_AXIS);

//Create a box with vertical layout
Box box4=new Box(BoxLayout.Y_AXIS);

//Create a window using JFrame with title ( Set JPanel layout using GridBagLayout )
JFrame frame=new JFrame("Set JPanel layout using GridBagLayout");

//Constructor
public SetJPanelLayoutToGridBagLayout()
{
 //Make text in label allign to right
 label.setHorizontalAlignment(SwingConstants.RIGHT);
 label2.setHorizontalAlignment(SwingConstants.RIGHT);

 //Set panel layout to GridBagLayout
 setLayout(gbl);

 //Field that will be use when display area is larger than component size.
 //It mean when it has some space between component, component will
 //enlarge to horizontal direction
 gbc.fill=GridBagConstraints.HORIZONTAL;

 /*
  *Add label into panel with top left corner of the label at crossing between
  *first horizontal and first vertical line.
  *It will take 4 grid for it's width
  *It will take 1 grid for it's height
  */
 addComponent(label,1,1,4,1);

 /*
  *Add label2 into panel with top left corner of the
  *label at crossing between
  *third horizontal and first vertical line.
  *It will take 4 grid for it's width
  *It will take 1 grid for it's height
  */
 addComponent(label2,3,1,4,1);

 /*
  *Add textField into panel with top left corner of the text field at
  *crossing between first horizontal and sixth vertical line
  *It will take 12 grid for it's width
  *It will take 1 grid for it's height
  */
 addComponent(textField,1,6,12,1);

 /*
  *Add textField2 into panel with top left corner of the text field at
  *crossing between third horizontal and sixth vertical line
  *It will take 3 grid for it's width
  *It will take 1 grid for it's height
  */
 addComponent(textField2,3,6,3,1);

 /*
  *Add button into panel with top left corner of the button at
  *crossing between fifth horizontal and fifth vertical line
  *It will take 5 grid for it's width
  *It will take 2 grid for it's height
  */
 addComponent(button,5,5,5,2);

 /*
  *Add button2 into panel with top left corner of the button at
  *crossing between fifth horizontal and eleventh vertical line
  *It will take 5 grid for it's width
  *It will take 2 grid for it's height
  */
 addComponent(button2,5,11,5,2);

 /*
  *Add a component that is invisible with 10 pixels width
  *and 10 pixels height into box1
  */
 box1.add(Box.createRigidArea(new Dimension(10,10)));

 /*
  *Add box1 into panel with top left corner of the box at
  *crossing between first horizontal and fifth vertical line
  *It will take 1 grid for it's width
  *It will take 3 grid for it's height
  */
 addComponent(box1,1,5,1,3);

 /*
  *Add a component that is invisible with 30 pixels width
  *and 10 pixels height into box2
  */
 box2.add(Box.createRigidArea(new Dimension(30,10)));

 /*
  *Add box2 into panel with top left corner of the box at
  *crossing between second horizontal and first vertical line
  *It will take 17 grid for it's width
  *It will take 1 grid for it's height
  */
 addComponent(box2,2,1,17,1);

 /*
  *Add a component that is invisible with 30 pixels width
  *and 10 pixels height into box3
  */
 box3.add(Box.createRigidArea(new Dimension(30,10)));

 /*
  *Add box3 into panel with top left corner of the box at
  *crossing between fourth horizontal and first vertical line
  *It will take 17 grid for it's width
  *It will take 1 grid for it's height
  */
 addComponent(box3,4,1,17,1);

 /*
  *Add a component that is invisible with 10 pixels width
  *and 10 pixels height into box4
  */
 box4.add(Box.createRigidArea(new Dimension(10,10)));

 /*
  *Add box4 into panel with top left corner of the box at
  *crossing between fifth horizontal and tenth vertical line
  *It will take 1 grid for it's width
  *It will take 2 grid for it's height
  */
 addComponent(box4,5,10,1,2);

 //Add panel into JFrame
 frame.add(this);

 //Set default close operation for JFrame
 frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

 //SetJFrame size
 frame.setSize(500,400);

 //Make JFrame center on the screen
 frame.setLocationRelativeTo(null);

 //Disble JFrame from resizable
 frame.setResizable(false);
 frame.setVisible(true);
}

//Method addComponent
public void addComponent(Component component, int row, int column, int width, int height)
{
 gbc.gridx=column;
 gbc.gridy=row;
 gbc.gridwidth=width;
 gbc.gridheight=height;
 gbl.setConstraints(component,gbc);
 add(component);
}

//Main method
public static void main(String[]args)
{
 SetJPanelLayoutToGridBagLayout sjpltgbl=new SetJPanelLayoutToGridBagLayout();
}
}

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**************************************************************

Tip for GridBagLayout

2009-01-24T00:27:00.004+08:00

GridBagLayout enable you to arrange component in more flexible way. What you need is only a piece of paper. After that, you draw grid and sketch your graphical user interface on the paper like image below.

Click here for it's source code

Tip for GridLayout

2009-01-23T23:47:00.005+08:00

GridLayout will arrange components into container from left to right like FlowLayout do. But what make it different to FlowLayout ? The answer is, it will arrange components in grid. See the image below. It represent a grid with 3 rows and 2 columns. First component will be put into first row and first column. Second component will be put into first row and second column. Third component will be put into second row and first column. Fourth component will be put into second row and second column. Fifth component will be put into third row and first column and last component will be put into third row and second column.

Example source code for GridLayout

Tip for BorderLayout

2009-01-23T23:17:00.003+08:00

BorderLayout is also a layout manager like FlowLayout. But, it not arrange components in container from left to right like FlowLayout do. It will arrange component in five part.

NORTH
SOUTH
CENTER
EAST
WEST

Example source code for BorderLayout

Tip for FlowLayout

2009-01-23T18:39:00.004+08:00

FlowLayout is use to arrange components in a container from left to right. If it reached at the end of the container, but there are still left other component, it will go to the next line in the container and start again arrange component from left to right.

Example of container : JFrame, JPanel, JWindow, JInternalFrame
(Use to hold other component)

Example of component : JPanel, JButton, JTextField, JCheckBox, JRadioButton

Example source code for FlowLayout

Set JTextField background image

2009-01-23T08:53:00.005+08:00

Complete source code below will show you, how to set image background in a JTextField. You can download image (textFieldBackgroundImage.jpg) that use in source code at below.

*******************************************************************
COMPLETE SOURCE CODE FOR : SetJTextFieldBackgroundImage.java
*******************************************************************


import javax.swing.*;

import java.awt.*;

public class SetJTextFieldBackgroundImage extends JTextField
{
public SetJTextFieldBackgroundImage()
{
 JFrame frame=new JFrame("Set JTextField background image");
 frame.add(this);
 frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 frame.setSize(300,65);
 frame.setLocationRelativeTo(null);
 frame.setResizable(false);
 frame.setVisible(true);
}

public void paint(Graphics g)
{
 setOpaque(false);

 //Image that will be set as JTextField background
 //I suggest, image that will be use is blur...
 //If image is locate at other location, you must put it's full location address.
 //For example : C:\\Documents and Settings\\evergreen\\Desktop\\textFieldBackgroundImage.jpg
 ImageIcon ii=new ImageIcon("textFieldBackgroundImage.jpg");
 Image i=ii.getImage();
 g.drawImage(i,0,0,this);
 super.paint(g);
}

public static void main(String[]args)
{
 SetJTextFieldBackgroundImage sjtfbi=new SetJTextFieldBackgroundImage();
}
}

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*******************************************************************

textFieldBackgroundImage.jpg

Set JButton background color on click

2009-01-23T07:42:00.002+08:00

Click here

Determine character is whitespace

2009-01-23T01:04:00.004+08:00

Complete source code below will show you, how to determine character is whitespace or not in java.

*******************************************************************
COMPLETE SOURCE CODE FOR : DetermineCharacterIsSpace.java
*******************************************************************


public class DetermineCharacterIsSpace
{
public static void main(String[]args)
{
 //Create a space character using char by press spacebar once between single quote(' ')
 //You can try change it's value by change it to a letter 'A' for example.
 char a=' ';

 //Determine created character is space or not
 //using method isWhitespace from class Character.
 //isWhitespace is a static method, so we don't need to create object when
 //we want to use it.
 if(Character.isWhitespace(a))
 {
  //Print (It is a whitespace) if character is a whitespace
  System.out.println("It is a whitespace");
 }
 else
 {
  //Print (It is not a whitespace) if character is not a whitespace
  System.out.println("It is not a whitespace");
 }
}
}

*******************************************************************
JUST COMPILE AND EXECUTE IT
*******************************************************************

Determine character is uppercase

2009-01-22T17:56:00.004+08:00

Complete source code below will show you, how to determine character is uppercase or not in java.

******************************************************************
COMPLETE SOURCE CODE FOR : DetermineCharacterIsUppercase.java
******************************************************************


public class DetermineCharacterIsUppercase
{
public static void main(String[]args)
{
 //Create a uppercase character using char with value(B)
 //You can try change it's value to letter(b)
 char a='B';

 //Determine created character is uppercase or not
 //using method isUpperCase from class Character.
 //isUpperCase is a static method, so we don't need to create object when
 //we want to use it.
 if(Character.isUpperCase(a))
 {
  //Print (It is an uppercase) if character is an uppercase
  System.out.println("It is an uppercase");
 }
 else
 {
  //Print (It is not an uppercase) if character is not an uppercase
  System.out.println("It is not an uppercase");
 }
}
}

******************************************************************
JUST COMPILE AND EXECUTE IT
******************************************************************

Determine character is lowercase

2009-01-22T17:00:00.004+08:00

Complete source code below will show you, how to determine character is lowercase or not in java.

**********************************************************************
COMPLETE SOURCE CODE FOR : DetermineCharacterIsLowercase.java
**********************************************************************


public class DetermineCharacterIsLowercase
{
public static void main(String[]args)
{
 //Create a lowercase character using char with value(b)
 //You can try change it's value to letter(B)
 char a='b';

 //Determine created character is lowercase or not
 //using method isLowerCase from class Character.
 //isLowerCase is a static method, so we don't need to create object when
 //we want to use it.
 if(Character.isLowerCase(a))
 {
  //Print (It is a lowercase) if character is a lowercase
  System.out.println("It is a lowercase");
 }
 else
 {
  //Print (It is not a lowercase) if character is not a lowercase
  System.out.println("It is not a lowercase");
 }
}
}

**********************************************************************
JUST COMPILE AND EXECUTE IT
**********************************************************************