从数硬币看线程安全

最新推荐文章于 2025-08-23 19:36:46 发布

转载最新推荐文章于 2025-08-23 19:36:46 发布 · 44 阅读

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原文链接：http://www.cnblogs.com/interfaceone/p/6641429.html

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#java

创建并启动100个线程，往balance中添加1个硬币，最后balance会为多少呢？

import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

public class AccountWithoutSync {
   private static Account account = new Account();

   public static void main(String[] args){
       ExecutorService executor = Executors.newCachedThreadPool();//线程池
       for(int i=0;i<100;i++){//执行100个线程
           executor.execute(new AddPennyTask());
       }
       executor.shutdown();
       while(!executor.isTerminated()){//确认100个线程关闭
       }
       System.out.println("what is the balance?"+account.getBalance());
   }

   public static class AddPennyTask implements Runnable{//內部類
       public void run(){
           account.deposit(1);
       }
   }

   public static class Account{//內部類
       private int balance = 0;
       public int getBalance() {
           return balance;
       }
       public void deposit(int amount){
           int newBalance = balance + amount;
           try{
               Thread.sleep(1);//1ms
           }catch(InterruptedException ex){

           }
           balance = newBalance;
       }
   }
}