How to swap two variables in one line in Java?

// Java program to swap two variables in single line

class Demo
{
   public static void main (String[] args)
   {
      int a = 6, b = 11;
      a = a ^ b ^ (b = a);
      System.out.println("After Swapping values of a and b are "
                          + a + " " + b);
   }
}

Output:

After Swapping values of x and y are 11 6

Explanation of above program:

Java always evaluate operands from left to right.

The left-hand operand of a binary operator in this case a ^ b appears to be fully evaluated before any part of the right-hand operand (b = a) is evaluated. Therefore,

Flow of evaluation:

a ^ b = 6 ^ 11 = 13

After this again a binary operation ^ is performed but for that right hand side of ^ is to be evaluated thereby assigning value of a to b and assign result of 13 ^ b to a.

a = 13 ^ b = 13 ^ 6 = 11

Now a is having value 11 and in the expression b is already ssigned with previous value of a i.e 6.

But a = (b=a) ^ b ^ a will not swap values because if the operator is a compound-assignment operator on left hand side, then evaluation of the left-hand operand includes both remembering the variable that the left-hand operand denotes and fetching and saving that variable's value for use in the implied binary operation.