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<String> 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<String> errRet;public LayerInitTask(int num, Vector<String> errRet) {this.threadNum = num;this.errRet = errRet;}@Overridepublic 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