What operator is ! in java?

The ! operator in Java represents logical negation, also known as negation. It converts the operand into a Boolean value and then returns its opposite value. It works on Boolean expressions or variables, returning false for true and true for false. The ! operator has higher precedence than relational and equality operators, but lower precedence than unary operators, and evaluates from right to left. It is often used to reverse Boolean logic, such as changing the state of a Boolean value, negating conditional statements, and creating Boolean expressions that satisfy multiple conditions simultaneously or the opposite.

The ! operator in Java

! The operator represents logical negation in Java, also known as taking opposite. It converts the operand to a Boolean value and returns its opposite value.

Syntax:

<code>!expression</code>

where expression is the Boolean expression or variable to be negated.

Operation:

! The operator performs the following operations:

1. Converts expression to a Boolean value.
2. If expression is true, return false.
3. If expression is false, return true.

Example:

<code>boolean flag = true;
boolean result = !flag; // result 为 false，因为 !true = false</code>

Special case:

When expression is null, the ! operator will throw Throws a NullPointerException.

Priority and associativity:

! The precedence of the operator is higher than the relational and equality operators, but lower than the unary operators (such as , -). It is right associative, which means it evaluates from right to left.

Usage:

! The operator is typically used to reverse the logic of a Boolean value. It can be used in various scenarios, such as:

• Set a Boolean value to its opposite value.
• Negative conditional statement.
• Create Boolean expressions where multiple conditions need to be true or false.

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