In Java, the increment and decrement operators are used to increase or decrease the value of a variable by 1. These operators are often used in loops and other situations where you need to modify a variable's value in a controlled manner.

• Increment & decrement operators can apply only for variables but not for constant values. otherwise, we will get a compile-time error
• We can't perform nesting of increment or decrement operator, otherwise, we will get compile time error
• For the final variables, we can't apply increment or decrement operators, otherwise, we will get compile-time error
• We can apply increment or decrement operators even for primitive data types except for boolean.
• ++variable: Increments the value of the variable by 1 and returns the updated value.
• --variable: Decrements the value of the variable by 1 and returns the updated value.
• variable++: Returns the current value of the variable, then increments it by 1.
• variable--: Returns the current value of the variable, then decrements it by 1.

Increment Operators

There are two types of increment operators available.

1. pre-increment
2. post-increment

Pre Increment Operator in Java

In the pre-increment operator, the variable is first incremented by 1 and then assigned to another variable.

Example

		
	class PreIncrementProgram{
		public static void main(String [] args){
			int x = 5;
			System.out.println(++x);//x=6
			int y = ++x;//x=7
			System.out.println(y);//7
		}
	}
			
	

Output :

	
	
		6
		7
	

Post Increment Operator in Java

In the post-increment operator, the variable is first used and assigned to another variable and then it will increase by 1.

Example

		
	class PostIncrementProgram{
		public static void main(String [] args){
			int x = 5;
			System.out.println(x++);//print 5 and increse by one now x=6
			int y = x++;//x=7,y==6
			System.out.println(x);//7
			System.out.println(y);//6
		}
	}
			
	

Output :

	
	
		5
		7
		6
	

Decrement Operator in java

there are two types of decrement operator available in java.

1. pre decrement in java
2. post decrement in java

Pre Decrement Operator in java

In pre-decrement operator, the variable is first decremented by 1 and then assigned to another variable.

Example

		
	class PreDecrementProgram{
		public static void main(String [] args){
			int x = 5;
			System.out.println(--x);//x=4
			int y = --x;//x=3
			System.out.println(y);//3
		}
	}
			
	

Output :

	
	
		4
		3
	

Post decrement Operator in java

In post-decrement operator, the variable is first used and assigned to another variable and then it will decrease by 1.

Example

		
	class PostDecrementProgram{
		public static void main(String [] args){
			int x = 5;
			System.out.println(x--);//print 5 and decrese by one now x=4
			int y = x--;//x=3,y==4
			System.out.println(x);//3
			System.out.println(y);//4
		}
	}
			
	

Output :

	
	
		5
		3
		4