java中把两个变量进行值交换，通过异或两次运算就能实现值互换。

package frank;
public class App
{
	public static void main(String[] args)
	{
		int a = 2;//00000000000000000000000000000010
		int b = 3;//00000000000000000000000000000011
		a = a ^ b;//00000000000000000000000000000001
		b = a ^ b;//00000000000000000000000000000010
		a = a ^ b;//00000000000000000000000000000011
		System.out.println(String.valueOf(a)+"---"+b);
	}
}