ThreadPoolExecutor异常处理

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java.util.concurrent包中的ThreadPoolExecutor，提供了java语言的线程池，你可以提交一个返回结果的任务（submit(Callable)，返回Future），或者执行一个不返回结果的任务（execute(Runnable)），但提交的任务可能会抛异常，这就需要处理异常：

1. 对于submit的任务，框架会将异常保持在future里，并包装在ExecutionException里，当调用Future.get()时，再次throw，这时可以调用ExecutionException.getCause()获取包装的exception，这种情况下，设置UncaughtExceptionHandler也不会被调用。

2. 对应execute的任务，会直接throw，可以设置一个UncaughtExceptionHandler，例如：

Java代码  

1. import java.lang.Thread.UncaughtExceptionHandler;  
2. import java.util.Random;  
3. import java.util.concurrent.CancellationException;  
4. import java.util.concurrent.ExecutionException;  
5. import java.util.concurrent.ExecutorService;  
6. import java.util.concurrent.Future;  
7. import java.util.concurrent.LinkedBlockingQueue;  
8. import java.util.concurrent.ThreadFactory;  
9. import java.util.concurrent.ThreadPoolExecutor;  
10. import java.util.concurrent.TimeUnit;  
11. import java.util.concurrent.atomic.AtomicInteger;  
12.   
13. public class ExecutorServiceDemo {  
14.   
15.     public static void testExecute() {  
16.         ExecutorService executors = new ThreadPoolExecutor(10, 20, 60, TimeUnit.SECONDS,  
17.                 new LinkedBlockingQueue<Runnable>(), new ThreadFactory() {  
18.                     final AtomicInteger threadNumber = new AtomicInteger(1);  
19.   
20.                     public Thread newThread(Runnable r) {  
21.                         Thread t = new Thread(Thread.currentThread().getThreadGroup(), r, "topPatternTasklet-thread"  
22.                                 + (threadNumber.getAndIncrement()));  
23.                         t.setUncaughtExceptionHandler(new UncaughtExceptionHandler() {  
24.   
25.                             public void uncaughtException(Thread t, Throwable e) {  
26.                                 System.out.println(e);  
27.                             }  
28.                               
29.                         });  
30.                         return t;  
31.                     }  
32.                 }, new ThreadPoolExecutor.CallerRunsPolicy());  
33.   
34.         final Random r = new Random();  
35.         for (int i = 0; i < 10; ++i) {  
36.             executors.execute(new Runnable() {  
37.   
38.                 public void run() {  
39.                     try {  
40.                         int ri = r.nextInt(1000);  
41.                         Thread.sleep(ri);  
42.                         if (ri % 3 == 0) {  
43.                             System.out.println("ri:" + ri);  
44.                             throw new RuntimeException("haha error!");  
45.                         }  
46.                         System.out.println(Thread.currentThread());  
47.                     } catch (InterruptedException e) {  
48.                     }  
49.                 }  
50.             });  
51.         }  
52.   
53.         executors.shutdown();  
54.         System.out.println("finished");   
55.     }  
56.     public static void main(String[] args) {  
57.         testExecute();  
58.     }  
59. }  

ThreadPoolExecutor异常处理

标签：shu   .com   返回   ++i   包装   tun   throwable   语言   wan   

原文地址：http://www.cnblogs.com/exmyth/p/7236977.html