java 交换两个变量的值

1. 定义临时变量
2. 通过算术运算
3. 通过位运算符实现
   新建 ExchangeTest

public class ExchangeTest {

    public static void main(String[] args) {
        ExchangeTest exchangeTest = new ExchangeTest();
//        exchangeTest.test01();
//        exchangeTest.test02();
        exchangeTest.test03();
    }

    
    public void test01(){
        int a = 10;
        int b = 20;
        int temp = a;  // 10
        a = b; // a:20
        b = temp; // b:10
        System.out.println("a=" + a + " b=" + b);
    }

    
    public void test02(){
        int a = 10;
        int b = 20;
        a = a + b; // a: 10 + 20 = 30
        b = a - b; // b: 30 - 20 = 10
        a = a - b; // 30 - 20 = 10
        System.out.println("a=" + a + " b=" + b);
    }

    
    public void test03(){
        int a = 10;
        int b = 20;
        a = a ^ b; // a改变值之后记录为a,为改变值的记录为a1    b改变值之后记录为b,为改变值的记录为b1
        b = a ^ b; // a1 ^ b ^ b  -> b = a1 = 10
        a = a ^ b; // a1 ^ b1 ^ a1  -> a = b1 = 20
        System.out.println("a=" + a + " b=" + b);
    }
}