执行者服务中的异常处理

Question

当我从学生姓名 archana 抛出异常时。根据我的理解 InvokeAll 等待所有任务完成然后 return 未来列表

我得到的输出是

 pool-1-thread-1 Helloprerna   
 pool-1-thread-2 Helloabc   
 HELLO SOMEERROR   
 Execution Completed

我希望显示其他任务输出，其中异常不是 thrown.Any 建议

public class Executor {

    public static void main(String args[]) throws InterruptedException{

        ExecutorService  executor=Executors.newFixedThreadPool(5);

        ArrayList<Student> list = new ArrayList<Student>();
        list.add(new Student("prerna"));
        list.add(new Student("abc"));
        list.add(new Student("archana"));
        list.add(new Student("def"));
        list.add(new Student("xyz"));
        list.add(new Student("ritu"));
        list.add(new Student("babita"));

        try {
            List<Future<String>> resultList=executor.invokeAll(list);
            for(Future<String> f:resultList){
                //if(f.isDone()){
                    System.out.println(f.get());
                //}
            }
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }catch (ExecutionException e) {
            // TODO Auto-generated catch block
            System.out.println("HELLO SOME ERROR");
            //e.printStackTrace();
        }

        executor.shutdown();
        executor.awaitTermination(10, TimeUnit.SECONDS);
          System.out.println("Execution Completed");

    }
}

.

public class Student implements Callable<String>{
    String name;
    public Student(String name) {
        super();
        this.name = name;
    }

    @Override
    public String call() throws Exception {
        // TODO Auto-generated method stub
        if(name=="archana"){
            throw new Exception();
        }
        return display(name);
    }

    private String display(String name2) {
        try {
        //  System.out.println(Thread.currentThread().getName());
            name2=Thread.currentThread().getName()+" Hello"+ name;
            Thread.sleep(1000);
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return name2;
    }

}

Answer 1

您可以在 try/catch 周围移动：

原文：

try {
    List<Future<String>> resultList=executor.invokeAll(list);
    for(Future<String> f:resultList){
    //  if(f.isDone()){

                System.out.println(f.get());

        //}
    }
} catch (InterruptedException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
}catch (ExecutionException e) {
    // TODO Auto-generated catch block
    System.out.println("HELLO SOME ERROR");
//  e.printStackTrace();
}

将是：

try {
    List<Future<String>> resultList=executor.invokeAll(list);
    for(Future<String> f:resultList){
        try{
            System.out.println(f.get());
        }catch (ExecutionException e) {
            System.out.println("HELLO SOME ERROR: " + e.getMessage());
        }
} catch (InterruptedException e) {
    e.printStackTrace();
}

所以在这里你会得到所有好的结果，你可以处理每个任务的异常执行。

Answer 2

这个模式应该是：主线程创建并调用从属线程，它应该 return ok 值或错误值（如果有任何错误）。然后主线程应该从奴隶那里收集结果并处理它们。

执行者服务中的异常处理

exception handling in executor service

java

multithreading

future

executorservice