来自.net的AggregateException在java中的等价物是什么？

Question

在.net中，AggregateException类允许抛出包含多个异常的异常。

例如，如果并行运行多个任务，并且其中一些任务因异常而失败，则可能需要抛出AggregateException。

java有没有等价的类？

我想要在以下情况下使用它：

public static void runMultipleThenJoin(Runnable... jobs) {
    final List<Exception> errors = new Vector<Exception>();
    try {
        //create exception-handling thread jobs for each job
        List<Thread> threads = new ArrayList<Thread>();
        for (final Runnable job : jobs)
            threads.add(new Thread(new Runnable() {public void run() {
                try {
                    job.run();
                } catch (Exception ex) {
                    errors.add(ex);
                }
            }}));

        //start all
        for (Thread t : threads)
            t.start();

        //join all
        for (Thread t : threads)
            t.join();            
    } catch (InterruptedException ex) {
        //no way to recover from this situation
        throw new RuntimeException(ex);
    }

    if (errors.size() > 0)
        throw new AggregateException(errors); 
}

Answer 1

我不知道有什么内置的或库的类，因为我以前从来没有想过要这样做(通常你只需要链接异常)，但是自己编写并不难。

您可能希望选择其中一个异常作为“主要”，这样它就可以用来填充堆栈跟踪等。

public class AggregateException extends Exception {

    private final Exception[] secondaryExceptions;

    public AggregateException(String message, Exception primary, Exception... others) {
        super(message, primary);
        this.secondaryExceptions = others == null ? new Exception[0] : others;
    }

    public Throwable[] getAllExceptions() {

        int start = 0;
        int size = secondaryExceptions.length;
        final Throwable primary = getCause();
        if (primary != null) {
            start = 1;
            size++;
        }

        Throwable[] all = new Exception[size];

        if (primary != null) {
            all[0] = primary;
        }

        Arrays.fill(all, start, all.length, secondaryExceptions);
        return all;
    }

}

Answer 2

Java7的Throwable.addSuppressed(Throwable)将做类似的事情，尽管它是为稍微不同的目的而构建的(try-with-resource)

Answer 3

您可以将多个taska表示为

List<Callable<T>> tasks

然后，如果你想让计算机真正并行使用它们

ExecutorService executorService = .. initialize executor Service
List<Future<T>> results = executorService.invokeAll ( ) ;

现在您可以遍历结果了。

try
{
     T val = result . get ( ) ;
}
catch ( InterruptedException cause )
{
     // this is not the exception you are looking for
}
catch ( ExecutionExeception cause )
{
     Throwable realCause = cause . getCause ( ) // this is the exception you are looking for
}

因此，realCause (如果存在)是在其关联任务中抛出的任何异常。