Let’s see how to use variables in JAVA in a simple tutorial.

Let’s see an example of variable declarations in JAVA:

public class Main {
	/**
	* @param args
	*/
	public static void main(String[] args) {
		byte aByte;
		short aShort;
		int anInt;
		long aLong;
		float aFloat;
		double aDouble;
		char aChar;
		boolean aBoolean;
		aByte = 123;
		aShort = 12345;
		anInt = 1234567890;
		aLong = 1000000000000000000L;
		aFloat = 9.12345678912345678912345678945123F;
		aDouble = 0.3333333333333333333333333333333333333333334;
		aChar = 65;
		aBoolean = true;
		System.out.println("aByte = " + aByte);
		System.out.println("aShort = " + aShort);
		System.out.println("anInt = " + anInt);
		System.out.println("aLong = " + aLong);
		System.out.println("aFloat = " + aFloat);
		System.out.println("aDouble = " + aDouble);
		System.out.println("aChar = " + aChar);
		System.out.println("aBoolean = " + aBoolean);
	}
}

Result:

aByte = 123

aShort = 12345

anInt = 1234567890

aLong = 1000000000000000000

aFloat = 9.123457

aDouble = 0.3333333333333333

aChar = A

aBoolean = true

Note the aChar value: A.

Indeed, in the ASCII table 65 (in decimal) is equal to the A character.

Note also the L at the end of the long variable value.