Java一元操作符++详解
废话不多说,直接上代码。
package com.coshaho.learn; /** * * OperatorLearn.java Create on 2016-11-13 下午8:38:15 * * 类功能说明: 深入理解++操作符 * * Copyright: Copyright(c) 2013 * Company: COSHAHO * @Version 1.0 * @Author coshaho */ public class OperatorLearn { // 一元操作符,赋值操作符,三目操作符从右向左运算,其他操作符从左向右运算 // ++x步骤:1.返回x+1;2.执行x = x + 1; // x++步骤:1.返回x;2.执行x = x + 1; public static void main(String[] args) { int x = 1; // 步骤1. 计算y(默认值0); // 步骤2. (x++)返回x值给临时变量c,为1; // 步骤3. x = x + 1,x为2; // 步骤4. 计算x,x为2; // 步骤5. y = 临时变量c + 2 = 1 + 2 = 3. int y = (x++) + x; System.out.println("x = " + x); System.out.println("y = " + y); x = 1; // 步骤1. 计算y(默认值0); // 步骤2. (++x)返回x+1值给临时变量c,为2; // 步骤3. x = x + 1,x为2; // 步骤4. 计算x,x为2; // 步骤5. y = 临时变量c + 2 = 2 + 2 = 4. y = (++x) + x; System.out.println("x = " + x); System.out.println("y = " + y); x = 1; // 步骤1. 计算y(默认值0); // 步骤2. 计算x,为1; // 步骤3. (++x)返回x+1值给临时变量c,为2; // 步骤4. x = x + 1,x为2; // 步骤5. y = 1 + c = 1 + 2 = 3. y = x + (++x); System.out.println("x = " + x); System.out.println("y = " + y); x = 1; // 步骤1. 计算y(默认值0); // 步骤2. 计算x,为1; // 步骤3. (x++)返回x值给临时变量c,为1; // 步骤4. x = x + 1,x为2; // 步骤5. y = 1 + c = 1 + 1 = 2. y = x + (x++); System.out.println("x = " + x); System.out.println("y = " + y); x = 1; // 1.计算x,为1; // 2.计算(x++)返回1给临时变量c // 3.x = x + 1,为2; // 4.计算x = 1 + c = 1 + 1 = 2; x += (x++); System.out.println("x = " + x); int[] xx = {1,3}; int i = 0; xx[i++] *= 2; System.out.println("xx[0] = " + xx[0] + ", xx[1] = " + xx[1]); xx = new int[]{1,3}; i = 0; xx[i++] = xx[i++] * 2; System.out.println("xx[0] = " + xx[0] + ", xx[1] = " + xx[1]); /** * 输出 * x = 2 y = 3 x = 2 y = 4 x = 2 y = 3 x = 2 y = 2 x = 2 xx[0] = 2, xx[1] = 3 xx[0] = 6, xx[1] = 3 */ } }