How to make a boolean variable switch between true and false every time a method is invoked?

Question

I am trying to write a method that when invoked, changes a boolean variable to true, and when invoked again, changes the same variable to false, etc.

For example: ca

Answer 1

private boolean negate(boolean val) {
    return !val;
}

I think that is what you are asking for??

Answer 2

value ^= true;

That is value xor-equals true, which will flip it every time, and without any branching or temporary variables.

Answer 3

Without looking at it, set it to not itself. I don't know how to code it in Java, but in Objective-C I would say

booleanVariable = !booleanVariable;

This flips the variable.