JAVA不借助中间变量交换2个变量的值

public static void main(String[] args){
/*方法一*/
int a = 3;
int b = 4;
a=a+b;
b=a-b;
a=a-b;
System.out.println("a="+a+",b="+b);
/*方法二利用位运算交换，效率很高*/
int aa=3;
int bb=4;
aa=aa^bb;
bb=bb^aa;
aa=aa^bb;
System.out.println("aa="+aa+",bb="+bb);
}