Set file type in JFileChooser

Complete source code below will show you, how set file type that should be display in a JFileChooser. Source code below will display all directories and text files only.

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

import javax.swing.filechooser.FileFilter;

import javax.swing.JFileChooser;

import java.io.File;

public class SetJFileChooserFileType
{
public SetJFileChooserFileType()
{
 //Create a file chooser from JFileChooser
 JFileChooser fileChooser=new JFileChooser();

 //Set file type that should be display by set JFileChooser's file filter
 fileChooser.setFileFilter(new TypeOfFile());

 //Show JFileChooser
 int a=fileChooser.showDialog(null,"Open Text File");
}

//Class TypeOfFile 
class TypeOfFile extends FileFilter
{
 //Type of file that should be display in JFileChooser will be set here
 //We choose to display only directory and text file
 public boolean accept(File f)
 {
  return f.isDirectory()||f.getName().toLowerCase().endsWith(".txt");
 }

 //Set description for the type of file that should be display
 public String getDescription()
 {
  return ".text files";
 }
}

public static void main(String[]args)
{
 SetJFileChooserFileType sjfcft=new SetJFileChooserFileType();
}
}

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

Set password length for JPasswordField

Complete source code below will show you, how you can set password length in JPasswordField. In source code below, we will enable user to enter only password that contains five characters.After that it will disable password field. User can delete entered password by press 'Backspace' key.

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

import javax.swing.*;

import javax.swing.event.*;

import java.awt.event.*;

import java.awt.FlowLayout;

public class SetPasswordLength implements CaretListener
{
//Create password field
JPasswordField passwordField=new JPasswordField(12);

JLabel label=new JLabel("Press Backspace to delete password");

JFrame frame;

//Create key listener that will listen when someone press Backspace key
KeyListener kl=new KeyAdapter()
{
 public void keyPressed(KeyEvent event)
 {
  if(event.getKeyCode()==KeyEvent.VK_BACK_SPACE)
  {
   passwordField.setEditable(true);
  
   label.show(false);
  
   frame.repaint();
  
   frame.validate();
  }
 }
};

public SetPasswordLength()
{
 label.show(false);

 passwordField.addCaretListener(this);

 passwordField.addKeyListener(kl);

 frame=new JFrame("Set password length");

 frame.setLayout(new FlowLayout());

 frame.add(passwordField);

 frame.add(label);

 frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

 frame.setSize(500,100);

 frame.setVisible(true);
}

//Listen for changes in the caret position
public void caretUpdate(CaretEvent event)
{
 int passwordLength=passwordField.getText().length();

 //If password length equal to five characters, password field will uneditable
 //You can change to any password length that you want by change 5 to any other value
 if(passwordLength==5)
 {
  passwordField.setEditable(false);
 
  label.show(true);
 
  frame.repaint();
 
  frame.validate();
 }
}

public static void main(String[]args)
{
 SetPasswordLength spl=new SetPasswordLength();
}
}

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

Add scroll bar to JTextArea

Complete source code below will show you, how to add scroll bar to JTextArea.You can use scroll pane constants like below to set your text area scroll bar.

**************
HORIZONTAL
**************
HORIZONTAL_SCROLLBAR_ALWAYS
HORIZONTAL_SCROLLBAR_AS_NEEDED
HORIZONTAL_SCROLLBAR_NEVER

**************
VERTICAL
**************
VERTICAL_SCROLLBAR_ALWAYS
VERTICAL_SCROLLBAR_AS_NEEDED
VERTICAL_SCROLLBAR_NEVER

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

import javax.swing.*;

public class AddScrollBarToJTextArea
{
public static void main(String[]args)
{
 //Create JTextArea
 JTextArea textArea=new JTextArea("Put your text here");

 //Create JScrollPane that will be use as JTextArea scrollbar from JTextArea object
 JScrollPane scrollBar=new JScrollPane(textArea,JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,JScrollPane.HORIZONTAL_SCROLLBAR_ALWAYS);

 //Create a window using JFrame
 JFrame frame=new JFrame("Add scrollbar to JTextArea");

 //add created JScrollPane into JFrame
 frame.add(scrollBar);

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

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

 //Make JFrame get to center
 frame.setLocationRelativeTo(null);

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

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

Set word wrap in JTextArea

Complete source code below will show you, how to set word wrap in JTextArea.

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

import javax.swing.*;

public class SetWordWrapInJTextArea
{
public static void main(String[]args)
{
 JTextArea textArea=new JTextArea();

 //Set word wrap in JTextArea
 textArea.setWrapStyleWord(true);

 //Set line wrap in JTextArea
 textArea.setLineWrap(true);

 JFrame frame=new JFrame("Set word wrap in JTextArea");

 frame.add(textArea);

 frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

 frame.setSize(500,500);

 frame.setLocationRelativeTo(null);

 frame.setVisible(true);
}
}

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

Set JTextArea background color to JFrame default color

Complete source code below will show you, how to set JTextArea background color same to JFrame default color.

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

import javax.swing.*;

import java.awt.Color;

public class SetJTextAreaBackgroundColorToJFrameColor
{
public static void main(String[]args)
{
 //Create a window using JFrame with title ( Set JTextArea background color to JFrame color )
 JFrame frame=new JFrame("Set JTextArea background color to JFrame color");

 //Get JFrame background color
 Color jframeColor=frame.getBackground();

 //Create a text area with initial text ( Put your text here )
 JTextArea textArea=new JTextArea("Put your text here");

 //Set text area background color same to JFrame background color
 textArea.setBackground(jframeColor);

 //Add created text area into JFrame
 frame.add(textArea);

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

 //Set JFrame size
 frame.setSize(600,500);

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

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

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

Easiest way to make JFrame center

Complete source code below will show you, the easiest way to make JFrame get to the center of screen by only one line of code. We will use method setLocationRelativeTo(null) to make our JFrame get to the center. Remember, when you want to use this code, you must put it after you set JFrame size.

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

import javax.swing.JFrame;

public class EasiestWayToMakeJFrameCenter
{
public static void main(String[]args)
{
 JFrame frame=new JFrame("Easiest way to make JFrame center");

 frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 frame.setSize(500,400);

 //setLocationRelativeTo(null) will make JFrame get to the center
 frame.setLocationRelativeTo(null);
 frame.setVisible(true);
}
}

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

Get default JFrame background color

Complete source code below will show you, how to get default JFrame background color and after that, it will print RED,GREEN,BLUE(RGB) value for the color.

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

import javax.swing.JFrame;

import java.awt.Color;

public class GetDefaultJFrameBackgroundColor
{
public static void main(String[]args)
{
 //Create a window using JFrame
 JFrame frame=new JFrame();

 //Get JFrame background color using method getBackground()
 Color frameBackgroundColor=frame.getBackground();

 //Get RED value from color
 int redValue=frameBackgroundColor.getRed();

 //Get GREEN value from color
 int greenValue=frameBackgroundColor.getGreen();

 //Get BLUE value from color
 int blueValue=frameBackgroundColor.getBlue();

 //Print RGB value that we get
 System.out.println("R : "+redValue);
 System.out.println("G : "+greenValue);
 System.out.println("B : "+blueValue);

 //You can check what color that match the RGB value that we get using 'Color picker' at above
}
}

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

Get default JPanel background color

Complete source code below will show you, how to get default JPanel background color and after that, it will print RED,GREEN,BLUE(RGB) value for the color.

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

import javax.swing.JPanel;

import java.awt.Color;

public class GetDefaultJPanelBackgroundColor
{
public static void main(String[]args)
{
 //Create a panel using JPanel
 JPanel panel=new JPanel();

 //Get panel background color using method getBackground()
 Color panelBackgroundColor=panel.getBackground();

 //Get RED value from color
 int redValue=panelBackgroundColor.getRed();

 //Get GREEN value from color
 int greenValue=panelBackgroundColor.getGreen();

 //Get BLUE value from color
 int blueValue=panelBackgroundColor.getBlue();

 //Print RGB value that we get
 System.out.println("R : "+redValue);
 System.out.println("G : "+greenValue);
 System.out.println("B : "+blueValue);

 //You can check what color that match the RGB value that we get using 'Color picker' at above
}
}

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

Get default JLabel background color

Complete source code below will show you, how to get default JLabel background color and after that, it will print RED,GREEN,BLUE(RGB) value for the color.

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

import javax.swing.JLabel;

import java.awt.Color;

public class GetDefaultJLabelBackgroundColor
{
public static void main(String[]args)
{
 //Create a label using JLabel
 JLabel label=new JLabel();

 //Get label background color using method getBackground()
 Color labelBackgroundColor=label.getBackground();

 //Get RED value from color
 int redValue=labelBackgroundColor.getRed();

 //Get GREEN value from color
 int greenValue=labelBackgroundColor.getGreen();

 //Get BLUE value from color
 int blueValue=labelBackgroundColor.getBlue();

 //Print RGB value that we get
 System.out.println("R : "+redValue);
 System.out.println("G : "+greenValue);
 System.out.println("B : "+blueValue);

 //You can check what color that match the RGB value that we get using 'Color picker' at above
}
}

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

Put JLabel into list

Complete source code below will show you, how to put JLabel into list. During my try using java i found no way to put JLabel into JList. So i try to create it on my own. I hope you enjoy what i share with you.

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

import javax.swing.*;

import java.awt.GridLayout;

public class AddJLabelIntoList
{
public static void main(String[]args)
{
 //Create label using JLabel that will be put into list
 JLabel label1=new JLabel("Duck");
 JLabel label2=new JLabel("Sheep");
 JLabel label3=new JLabel("Cow");
 JLabel label4=new JLabel("Buffalo");
 JLabel label5=new JLabel("Horse");
 JLabel label6=new JLabel("Goat");

 //Create panel that will be use to put all label into it
 JPanel panel=new JPanel(new GridLayout(6,1));

 //Add all created label into panel
 panel.add(label1);
 panel.add(label2);
 panel.add(label3);
 panel.add(label4);
 panel.add(label5);
 panel.add(label6);

 //Create scroll bar for created panel
 //Vertical scrollbar always show
 //Horizontal scrollbar never show
 JScrollPane scrollBar=new JScrollPane(panel,JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);

 //Create window using JFrame with title ( Add JLabel into list )
 JFrame frame=new JFrame("Add JLabel into list");

 //Add created scroll bar into JFrame
 frame.add(scrollBar);

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

 //Set JFrame size
 frame.setSize(400,100);

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

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