Java自增自减-中间变量缓存

public class Demo {
    public static  void main(String[] args){
        method_1();
        method_2();
    }
    private static void method_1(){
        int j = 0;
        for(int i=0;i<100;i++){
            j = j++;
        }
        System.out.println("method_1---"+j);
    }
    private static void method_2(){
        int j = 0;
        for(int i=0;i<100;i++){
            j = ++j;
        }
        System.out.println("method_2---"+j);
    }
}

method_1---0  
method_2---100 

j = j++;
// 转化为下面代码
{
  int temp = j; 
  j = j + 1; 
  j = temp;
}

j = ++j;
// 转化为下面代码
{
  j = j + 1;
  int temp = j;
  j = temp; 
}