java进阶 实验二.doc

《Java语言进阶》 实 验 报 告（2） 学院：计算机与信息学院 专业：计算机科学与技术 学号： 姓名： 指导老师： 一、实验目的： 1. 理解多线程的原理和机制 2. 掌握Java内置多线程编程接口和相关的类 二、实验内容： 1. Write a program that launches 1000 threads. Each thread adds 1 to a variable sum that initially is 0. You need to pass sum by reference to each thread. In order to pass it by reference, define an Integer wrapper object to hold sum. Run the program with and without synchronization to see its effect. 2. .分析代码并解释 三、实验要求： 1、认真执行每一个步骤的，并作好记录。 2、实验报告中给出配置的详细步骤和重要的截图。 五、实验步骤： 1. Write a program that launches 1000 threads. Each thread adds 1 to a variable sum that initially is 0. You need to pass sum by ref- erence（ to each thread. In order to pass it by reference, define an Integer wrapper object to hold sum. Run the program with and without synchroniza- tion to see its effect. 2. dgd?????????o pass sum by ref- 运行下列代码，记录结果，并分析死锁的原因 // Exercise29_11.java: Demonstrate dead lock public class Exercise29_11 { private Object object1 = new Object(); private Object object2 = new Object(); public static void main(String[] args) { Exercise29_11 test = new Exercise29_11(); } public Exercise29_11() { new Thread1().start(); new Thread2().start(); } class Thread1 extends Thread { public void run() { synchronized (object1) { // do something try { Thread.sleep(100); } catch (InterruptedException ex) { } System.out.println(Attempt to acquire a lock on object2); synchronized (object2) { // do something } } } } class Thread2 extends Thread { public void run() { synchronized (object2) { // do something try { Thread.sleep(100); } catch (InterruptedException ex) { } System.out.println(Attempt to acquire a lock on object1); synchronized (object1) { // do something } } } } }