Java determine prime number

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.

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COMPLETE SOURCE CODE FOR : JavaDeterminePrimeNumber.java
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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");
  }
 }
}

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JUST COMPILE AND EXECUTE IT
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Read floating point number user input in java

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

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COMPLETE SOURCE CODE FOR : ReadFloatingPointNumberUserInput.java
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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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JUST COMPILE AND EXECUTE IT
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Get numbers of character in a string

Complete source code below will show you, how to get numbers of character that contain in a String. If you compile and execute source code below, you will get numbers of character is equal to 15 not 14. This is because the whitespace in a String also count.

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COMPLETE SOURCE CODE FOR : GetNumbersOfCharacterInAString.java
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public class GetNumbersOfCharacterInAString
{
public static void main(String[]args)
{
 //Create a String
 //You can change to other String that you want
 String a="Hello everybody";

 //Get numbers of character in created String and store it in int variable
 int numbersOfCharacter=a.length();

 //Print result
 System.out.println("Numbers of character is : "+numbersOfCharacter);
}
}

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JUST COMPILE AND EXECUTE IT
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Get number of screen

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COMPLETE SOURCE CODE FOR : GetNumbersOfScreenInJava.java
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import java.awt.GraphicsEnvironment;
import java.awt.GraphicsDevice;

public class GetNumbersOfScreenInJava
{
 public static void main(String[]args)
 {
  GraphicsEnvironment myGraphicsEnvironment=GraphicsEnvironment.getLocalGraphicsEnvironment();
  GraphicsDevice[]storeAllScreen=myGraphicsEnvironment.getScreenDevices();
  
  System.out.println("THE NUMBERS OF SCREEN IN MY COMPUTER IS : "+storeAllScreen.length);
 }
}

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JUST COMPILE AND EXECUTE IT
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