Unary Operator | Java

Unary operators in Java are operators that operate on a single operand. They are used to perform various operations such as incrementing/decrementing a value, negating a value, or inverting the bits of a value. Here are the main unary operators in Java:

1. Unary Plus (+):

   • Indicates a positive value. While it doesn't change the sign of positive numbers, it can be used to emphasize the positive sign.

    int x = 5;
    int result = +x; // result is 5

1. Unary Minus (-):

   • Negates the value of its operand.

    int y = 8;
    int result = -y; // result is -8

1. Increment (++):

• Increases the value of its operand by 1.

•   int a = 3;
    a++; // a is now 4
  

There are two types of implement operators -

• Post Increment: First initialise then increase.

• Pre Increment: First increase then initialise.

For example -

1. Decrement (--):

• Decreases the value of its operand by 1.

•   int b = 7;
    b--; // b is now 6
  

There are two types of implement operators -

• Post Increment: First initialise then increase.

• Pre Increment: First increase then initialise.

For example -

It's important to note that the increment and decrement operators can be used as a prefix (++a or --a) or a postfix (a++ or a--). The difference between the two lies in when the increment or decrement is applied in relation to the surrounding expression.

1. Logical Complement (!):

• Inverts the logical state of its operand. If the operand is true, the result is false, and if the operand is false, the result is true.

• This operator is only applicable for boolean.

•   boolean flag = true;
    boolean result = !flag; // result is false
  

• Bitwise Complement (~):

  • Inverts the bits of its operand, changing 1s to 0s and vice versa.

  • This operator is only applicable for integral not for boolean.

•   int number = 5; // binary: 0000 0000 0000 0000 0000 0000 0000 0101
    int result = ~number; // binary: 1111 1111 1111 1111 1111 1111 1111 1010 (-6 in decimal)
  

Unary operators are essential in various programming scenarios, and they play a crucial role in expressions and statements. Understanding how these operators work is fundamental for writing efficient and correct Java code.