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详解Java中多线程异常捕获Runnable的实现

时间:2017-10-28 编辑:猪哥 来源:一聚教程网

详解Java中多线程异常捕获Runnable的实现

1、背景:

        Java 多线程异常不向主线程抛,自己处理,外部捕获不了异常。所以要实现主线程对子线程异常的捕获。
2、工具:

        实现Runnable接口的LayerInitTask类,ThreadException类,线程安全的Vector
3、思路:

       向LayerInitTask中传入Vector,记录异常情况,外部遍历,判断,抛出异常。

4、代码:     

package step5.exception; 
 
import java.util.Vector; 
import java.util.concurrent.ExecutorService; 
import java.util.concurrent.Executors; 
import java.util.concurrent.TimeUnit; 
 
import com.autonavi.pds.core.incre.impl.LayerInitTask; 
 
public class ThreadException { 
 
  public static void main(String[] args) { 
    try { 
      Vector errRet = new Vector(); 
      ExecutorService pool = Executors.newFixedThreadPool(6); 
      for (int i = 0; i < 6; ++i) { 
        pool.execute(new LayerInitTask(i, errRet)); 
      } 
      pool.shutdown(); 
      pool.awaitTermination(1, TimeUnit.DAYS); 
       
      if (errRet.size() > 0) { 
        System.out.println("根据返回值捕获:exception"); 
        throw new RuntimeException( "入库失败!"); 
      } 
       
    } catch (Exception e) { 
      System.out.println("根据抛出异常捕获:exception"); 
      throw new RuntimeException( "入库失败!"); 
    } 
    System.out.println("-----入库成功,发成功完成工作邮件--------"); 
  } 
 
} 
package step5.exception; 
 
import java.util.Vector; 
 
public class LayerInitTask implements Runnable { 
  private int threadNum; 
  private Vector errRet; 
 
  public LayerInitTask(int num, Vector errRet) { 
    this.threadNum = num; 
    this.errRet = errRet; 
  } 
 
  @Override 
  public void run() { 
    try { 
      if (this.threadNum == 3) { 
        throw new RuntimeException( this.threadNum + ":数据格式有误."); 
      } 
      System.out.println(this.threadNum + ":刷表成功"); 
    } catch (Exception e) { 
      this.errRet.add("线程:" + this.threadNum + "运行异常!"); 
      throw new RuntimeException( this.threadNum + ":刷表失败"); 
    } 
  } 
 
} 

5、结果:

Exception in thread "pool-1-thread-4" java.lang.RuntimeException: 3:刷表失败 
  at step5.exception.LayerInitTask.run(LayerInitTask.java:23) 
  at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) 
  at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) 
  at java.lang.Thread.run(Unknown Source) 
Exception in thread "main" java.lang.RuntimeException: 入库失败! 
  at step5.exception.ThreadException.main(ThreadException.java:27) 
2:刷表成功 
1:刷表成功 
5:刷表成功 
0:刷表成功 
4:刷表成功 
根据返回值捕获:exception 
根据抛出异常捕获:exception 

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