Unary Operators in Java

In Java, unary arithmetic operators are used to increasing or decreasing the value of an operand.

OperatorDescription
+Unary plus operator; indicates positive value
Unary minus operator; negates an expression
++Increment operator; increments a value by 1
– –Decrement operator; decrements a value by 1
!Logical complement operator; inverts the value of a boolean

1. Plus Operator(+)

It is used to represent positive values. Usually, we do not write the operator before the operand. Hence, it is optional.

package octopuscodes.com.demo;

public class Demo {

	public static void main(String[] args) {
		int number1 = 4;
		System.out.println("Number 1: " + number1);

		int result1 = +number1;
		System.out.println("After unary plus operation result 1 is " + result1);

		int number2 = -9;
		System.out.println("Number 2: " + number2);

		int result2 = +number2;
		System.out.println("After unary plus operation result 2 is " + result2);
	}

}
Number 1: 4
After unary plus operation result 1 is 4
Number 2: -9
After unary plus operation result 2 is -9
 

2. Minus Operator(-)

It is used to convert a positive value into a negative one.

package octopuscodes.com.demo;

public class Demo {

	public static void main(String[] args) {
		int number1 = 4;
		System.out.println("Number 1: " + number1);

		int result1 = -number1;
		System.out.println("After unary minus operation result 1 is " + result1);

		int number2 = -9;
		System.out.println("Number 2: " + number2);

		int result2 = -number2;
		System.out.println("After unary minus operation result 2 is " + result2);
	}

}
Number 1: 4
After unary minus operation result 1 is -4
Number 2: -9
After unary minus operation result 2 is 9
 

3. Increment Operator(++)

It is used to increment the value of an operand by one. The operator can be applied before or after an operand.

  • Pre-increment Operator: If an increment operator is written before (prefix) the operand is known as pre-increment.
  • Post-increment Operator: If an increment operator is written after (postfix) the operand is known as post-increment.
package octopuscodes.com.demo;

public class Demo {

	public static void main(String[] args) {
		int number = 4;
		System.out.println("Number: " + number);

		++number;
		System.out.println("After Pre-increment operation number is " + number);

		number++;
		System.out.println("After Post-increment operation number is " + number);
	}

}
Number: 4
After Pre-increment operation number is 5
After Post-increment operation number is 6
 

4. Decrement operator(– –)

It is used to decrement the value of an operand by 1. The operator can be applied before or after an operand.

  • Pre-decrement Operator: If a decrement operator is written before (prefix) the operand is known as pre-decrement.
  • Post-decrement Operator: If a decrement operator is written after (postfix) the operand is known as post-decrement.
package octopuscodes.com.demo;

public class Demo {

	public static void main(String[] args) {
		int number = 4;
		System.out.println("Number: " + number);

		--number;
		System.out.println("After Pre-decrement operation number is " + number);

		number--;
		System.out.println("After Post-decrement operation number is " + number);
	}

}
Number: 4
After Pre-decrement operation number is 3
After Post-decrement operation number is 2
 

5. Logical Complement Operator(!)

A logical Complement Operator is used to reverse the value of a Boolean value. It means that if the value of an operand is true, then the complement of the operator will be false and vice-versa.

package octopuscodes.com.demo;

public class Demo {

	public static void main(String[] args) {
		boolean status1 = true;
		System.out.println("Status1: " + status1);

		status1 = !status1;
		System.out.println("After logical complement operation status 1 is " + status1);

		boolean status2 = false;
		System.out.println("Status2: " + status2);

		status2 = !status2;
		System.out.println("After logical complement operation status 2 is " + status2);
	}

}
Status1: true
After logical complement operation status 1 is false
Status2: false
After logical complement operation status 2 is true

Best Laptops for Programming