可见仍无规律可循，说明线程池的多线程是线程异步的。

package first_3;
import java.util.concurrent.*;
public class AccountWithoutDSync {private static Account account = new Account();public static void main(String args[]) {ExecutorService executor = Executors.newCachedThreadPool();//Creat and launch 100 threadsfor (int i = 0; i < 100; i++) {executor.execute(new AddAPennyTask());}executor.shutdown();//Wait until all tasks are finishedwhile (!executor.isTerminated()) {}System.out.println("What is balance? " + account.getBalance());}//A thread for adding a penny to the accountprivate static class AddAPennyTask implements Runnable {public void run() {account.deposit(1);}}//An inner class for accountprivate static class Account {private int balance = 0;public int getBalance() {return balance;}public void deposit(int amount) {int newBalance = balance + amount;//This delay is deliberately added to magnify the//data-corruption problem and make it easy to see.try {Thread.sleep(5);} catch (InterruptedException ex) {}balance = newBalance;}}
}

程序3： 

package first_3;
import java.util.concurrent.*;
public class AccountWithoutDSync {private static Account account = new Account();public static void main(String args[]) {ExecutorService executor = Executors.newCachedThreadPool();//Creat and launch 100 threadsfor (int i = 0; i < 100; i++) {executor.execute(new AddAPennyTask());}executor.shutdown();//Wait until all tasks are finishedwhile (!executor.isTerminated()) {}System.out.println("What is balance? " + account.getBalance());}//A thread for adding a penny to the accountprivate static class AddAPennyTask implements Runnable {public void run() {account.deposit(1);}}//An inner class for accountprivate static class Account {private int balance = 0;public int getBalance() {return balance;}public void deposit(int amount) {int newBalance = balance + amount;//This delay is deliberately added to magnify the//data-corruption problem and make it easy to see.try {Thread.sleep(5);} catch (InterruptedException ex) {}balance = newBalance;}}
}

(2). 编写Java应用程序实现如下功能：第一个线程输出数字1,2,..,12，第二个线程输出英文单词数字和月份One January, Two February, …, Twelve December，输出的顺序和格式为1OneJanuary2TwoFebruary...12TwelveDecember，即每1个数字紧跟着2个英文单词的方式。要求线程间实现通信。要求采用实现Runnable接口和Thread类的构造方法的方式创建线程，而不是通过Thread类的子类的方式。在报告中附上程序截图、运行结果截图和详细的文字说明。（15分）

这题最主要的还是线程之间的通信，在每个线程

输出相应的数字或字符后，在下一个输出前，都要判断是否要wait，才能保证相互的连续性

源代码如下：

首先是实现两者通信的类（单独开了一个包）：

其中定义了两个线程的进度timeOf...;然后先定义了一个String类型的数组month来使后面输出方便，再就是分别定义了synchronized 下的printNumber和printChatrs方法来使两线程同时进行两着主语句相差不大，printChars下定义了一个index来记录访问month的下标，注意一下两线程的输出顺序（再if里面注意判断）。

package second;
public class Connect {int timesOfInt = 1;int timesOfString = 1;String []month = {"One January", "Two  February", "Three March", "Four April", "Five May","Six June", "Seven July", "Eight August", "Nine September", "Ten October", "Eleven November", "Twelve December"};//先定义一下月份，方便输出synchronized void printNumber() {//线程1实现的输出1到12for (timesOfInt = 1; timesOfInt <= 12; timesOfInt++) {if (timesOfInt > timesOfString) //对应的字母未输出{try {wait();}catch (InterruptedException ex) {}}System.out.print(timesOfInt);notify();//输出后唤醒另一个线程}}synchronized void printChars() {//线程2输出One January到Twelve Decemberint index = 0;//记录month的下标for (timesOfString = 1; timesOfString <= 12; timesOfString++) {if (timesOfInt <= timesOfString) {//相应数字未输出try {wait();}catch (InterruptedException ex) {}}System.out.print(month[index++]+" ");//加个空格输出美观点notify();//唤醒另一个线程}}
}

然后在主运行的类下定义了两个方法printInt和printString均继承了Runnable接口，通过它们来调用非静态Connect中的方法，main类大体就只是调用：

package second;
class printInt implements  Runnable{Connect connect;//创建了connect类实例为了调用非static方法printInt (Connect connect1){connect=connect1;}public void run(){connect.printNumber();}//实现Ruunable接口
}
class printString implements Runnable{Connect connect;//创建了connect类实例为了调用非static方法printString(Connect connect1){connect=connect1;}public void run(){connect.printChars();}//实现Ruunable接口
}
public class second{    public static void main(String args[]){Connect connect=new Connect();//同一connect创建线程确保通信Thread threadA=new Thread(new printInt(connect));//Thread方法实现接口Thread threadB=new Thread(new printString(connect));threadA.start();threadB.start();}
}

(3). 编写Java应用程序实现如下功能：创建工作线程，模拟银行现金账户取款操作。多个线程同时执行取款操作时，如果不使用同步处理，会造成账户余额混乱，要求使用syncrhonized关键字同步代码块，以保证多个线程同时执行取款操作时，银行现金账户取款的有效和一致。要求采用实现Runnable接口和Thread类的构造方法的方式创建线程，而不是通过Thread类的子类的方式。在报告中附上程序截图、运行结果截图和详细的文字说明。（25分）

这道题很明显用syncrhonized的目的是，存钱时使得这次存款对应的输出余额相对应，不要让同时存的另一个数额也加进这次的余额计算中，所以采用syncrhonized关键字实现

源代码如下：

package third;
import java.util.*;
class Account implements  Runnable{private double account;//账户总额private String name;//账户名public double outAccount;//取款Account(double money,String s){account=money;name=s;}void setOutAccount(){System.out.print("请输入要取款的金额：");Scanner scanner=new Scanner(System.in);outAccount=scanner.nextDouble();}public synchronized void run(){setOutAccount();//outAccount记录这次要取的数目if(account

package four;
class East implements Runnable{private String name;//过桥人的名字private int num;//记录第num+1个人过桥（因为num当输出了）public void setEast(int num){//初始化我搞这了String s=Integer.toString(num);name="E"+s;this.num=num;}public void run(){//实现RunnableSystem.out.println(name+"正在过桥......");//输出过桥者的信息if(num==19)System.out.println("东边的人全部过桥啦！");//最后一人过桥则输出提}
}
class West implements Runnable{//与East类似的定义private String name;private int num;public void setWest(int num){//过桥者String s=Integer.toString(num);name="W"+s;this.num=num;}public void run(){System.out.println(name+"正在过桥......");//输出过桥者的信息if(num==19)//最后一人过桥则输出提示System.out.println("西边的人全部过桥啦！");}
}
public class Bridge {public static void main(String []args){for(int i=0;i<10;i++){int count=0;East []east=new East[20];West []west=new West[20];//定义桥的东西边各20个人Thread []threadWest=new Thread[20];Thread []threadEest=new Thread[20];//定义两边的线程for(int j=0;j<20;j++){east[j]=new East();east[j].setEast(j);threadEest[j]=new Thread();threadEest[j]=new Thread(east[j]);west[j]=new West();west[j].setWest(j);threadWest[j]=new Thread();threadWest[j]=new Thread(west[j]);//初始化}for(int j=0;j<20;j++){threadWest[j].start();threadEest[j].start();//开始}System.out.println("第"+(i+1)+"一波结束啦！");System.out.println("******分割******");}}
}