java线程：几个实用的线程工具类

 

java线程：几个实用的线程工具类

分类： java_线程 2012-07-04 16:29  89人阅读  评论(0)  收藏  举报

CyclicBarrier

[java]  view plain copy

1. import java.util.concurrent.CyclicBarrier;  
2. import java.util.concurrent.ExecutorService;  
3. import java.util.concurrent.Executors;  
4.   
5. /** 
6.  * @author amber2012 
7.  *  
8.  * CyclicBarrier: 
9.  * 表示线程彼此等待，等所有的线程都集合后，才开始做任务 
10.  *  
11.  */  
12. public class CyclicBarrierTest {  
13.   
14.     public static void main(String[] args) {  
15.         ExecutorService service = Executors.newCachedThreadPool();  
16.         final  CyclicBarrier cb = new CyclicBarrier(3);  
17.         for(int i=0;i<3;i++){  
18.             Runnable runnable = new Runnable(){  
19.                     public void run(){  
20.                     try {  
21.                         Thread.sleep((long)(Math.random()*10000));    
22.                         System.out.println("线程" + Thread.currentThread().getName() +   
23.                                 "即将到达集合地点1，当前已有" + (cb.getNumberWaiting()+1) + "个已经到达，" + (cb.getNumberWaiting()==2?"都到齐了，继续走啊":"正在等候"));                         
24.                         cb.await();  
25.                           
26.                         Thread.sleep((long)(Math.random()*10000));    
27.                         System.out.println("线程" + Thread.currentThread().getName() +   
28.                                 "即将到达集合地点2，当前已有" + (cb.getNumberWaiting()+1) + "个已经到达，" + (cb.getNumberWaiting()==2?"都到齐了，继续走啊":"正在等候"));  
29.                         cb.await();   
30.                         Thread.sleep((long)(Math.random()*10000));    
31.                         System.out.println("线程" + Thread.currentThread().getName() +   
32.                                 "即将到达集合地点3，当前已有" + (cb.getNumberWaiting() + 1) + "个已经到达，" + (cb.getNumberWaiting()==2?"都到齐了，继续走啊":"正在等候"));                       
33.                         cb.await();                       
34.                     } catch (Exception e) {  
35.                         e.printStackTrace();  
36.                     }                 
37.                 }  
38.             };  
39.             service.execute(runnable);  
40.         }  
41.         service.shutdown();  
42.     }  
43. }  

CountDownLatch：

[java]  view plain copy

1. import java.util.concurrent.CountDownLatch;  
2. import java.util.concurrent.ExecutorService;  
3. import java.util.concurrent.Executors;  
4.   
5. /** 
6.  * @author amber2012 
7.  *  
8.  * CountDownLatch： 
9.  * 好比倒计时计数器，调用CountDownLatch对象的CountDown方法就将计数器减1，当计数器到达0时，则所有等待线程 
10.  * 或单个等待线程开始执行。 
11.  */  
12. public class CountdownLatchTest {  
13.   
14.     public static void main(String[] args) {  
15.       
16.         ExecutorService service = Executors.newCachedThreadPool();  
17.         // 创建两个计数器，cdOrder的初始值为1，cdAnswer初始值为3  
18.         final CountDownLatch cdOrder = new CountDownLatch(1);  
19.         final CountDownLatch cdAnswer = new CountDownLatch(3);        
20.           
21.         for(int i=0;i<3;i++){  
22.             Runnable runnable = new Runnable(){  
23.                     public void run(){  
24.                     try {  
25.                         System.out.println("线程" + Thread.currentThread().getName() + "正准备接受命令");                          
26.                         cdOrder.await(); // 所有的线程都在此等待，并希望被其他线程调用cdOrder.countDown()激活，在这里由主线程激活  
27.                           
28.                         System.out.println("线程" + Thread.currentThread().getName() + "已接受命令");                                
29.                         Thread.sleep((long)(Math.random()*10000));    
30.                           
31.                         System.out.println("线程" + Thread.currentThread().getName() + "回应命令处理结果");                         
32.                         cdAnswer.countDown();// cdAnswer计数器的初始值为3，，三个线程到达后调用cdAnswer.countDown()到计数为0，激活主线程  
33.                     } catch (Exception e) {  
34.                         e.printStackTrace();  
35.                     }                 
36.                 }  
37.             };  
38.             service.execute(runnable);  
39.         }         
40.           
41.         try {  
42.             Thread.sleep((long)(Math.random()*10000));  
43.           
44.             System.out.println("线程" + Thread.currentThread().getName() + "即将发布命令");                       
45.             cdOrder.countDown();// 主线程将cdOrder计数器减1  
46.               
47.             System.out.println("线程" + Thread.currentThread().getName() + "已发送命令，正在等待结果");     
48.             cdAnswer.await();// 主线程正在等待，希望被其他线程激活  
49.               
50.             System.out.println("线程" + Thread.currentThread().getName() + "已收到所有响应结果");    
51.         } catch (Exception e) {  
52.             e.printStackTrace();  
53.         }                 
54.         service.shutdown();  
55.     }  
56. }  

Exchanger：

[java]  view plain copy

1. import java.util.concurrent.Exchanger;  
2. import java.util.concurrent.ExecutorService;  
3. import java.util.concurrent.Executors;  
4.   
5. /** 
6.  * @author amber2012 
7.  *  
8.  * Exchanger: 
9.  * 用于实现两个人之间的数据交换，每个人在完成一定的事务后想与对方交换数据，第一个先拿出数据的人将一直等待第二 
10.  * 个人拿着数据到来时，才能彼此交换数据。 
11.  */  
12. public class ExchangerTest {  
13.   
14.     public static void main(String[] args) {  
15.         ExecutorService service = Executors.newCachedThreadPool();  
16.         final Exchanger exchanger = new Exchanger();  
17.           
18.         service.execute(new Runnable(){  
19.             public void run() {  
20.                 try {                 
21.                     String data1 = "zxx";  
22.                     System.out.println("线程" + Thread.currentThread().getName() + "正在把数据" + data1 +"换出去");  
23.                     Thread.sleep(1000L);  
24.                       
25.                     String data2 = (String)exchanger.exchange(data1);  
26.                     System.out.println("线程" + Thread.currentThread().getName() + "换回的数据为" + data2);  
27.                 }catch(Exception e){  
28.                 }  
29.             }     
30.         });  
31.           
32.         service.execute(new Runnable(){  
33.             public void run() {  
34.                 try {                 
35.                     String data1 = "lhm";  
36.                     System.out.println("线程" + Thread.currentThread().getName() + "正在把数据" + data1 +"换出去");  
37.                     Thread.sleep(2000L);                      
38.                       
39.                     String data2 = (String)exchanger.exchange(data1);  
40.                     System.out.println("线程" + Thread.currentThread().getName() + "换回的数据为" + data2);  
41.                 }catch(Exception e){  
42.                 }                 
43.             }     
44.         });       
45.     }  
46. }