Java中关于i++与++i的问题

在《Java程序员面试宝典》里面有提到i++这个部分，j++是一个依赖于java里面的“中间缓存变量机制”来实现的。通俗的说

++在前就是“先加后赋”(++j)

++在后就是“先赋后加”(j++)

 

package cn.xy.test;

public class TestPlus
{
    private static int a()
    {
        int i = 10;
        int a = 0;
        a = i++ + i++;

        // temp1 = i; 10
        // i = i + 1; 11
        // temp2 = i; 11
        // i = i + 1; 12
        // a = temp1 + temp2 = 21;
        return a;
    }

    private static int b()
    {
        int i = 10;
        int b = 0;
        b = ++i + ++i;

        // i = i + 1; 11
        // temp1 = i; 11
        // i = i + 1; 12
        // temp2 = i; 12
        // b = temp1 + temp2 = 23;
        return b;
    }

    private static int c()
    {
        int i = 10;
        int c = 0;
        c = ++i + i++;

        // i = i + 1; 11
        // temp1 = i; 11
        // temp2 = i 11
        // i = i + 1; 12
        // c = temp1 + temp2 = 22
        return c;
    }

    private static int d()
    {
        int i = 10;
        int d = 0;
        d = i++ + ++i;

        // temp1 = i; 10
        // i = i + 1; 11
        // i = i + 1; 12
        // temp2 = i; 12
        // d = temp1 + temp2 = 22;
        return d;
    }

    public static void main(String[] args)
    {
        System.out.println(a());
        System.out.println(b());
        System.out.println(c());
        System.out.println(d());
    }
}

原帖地址:http://blog.csdn.net/zlqqhs/article/details/8288800