JMS超时处理方案2

/**
     * set client id
     * @param conn jms connection
     * @param timeout timeout
     * @param unit time unit
     * @return Boolean true or false
     * @throws LogCollectionException LogCollectionException
     * @throws IOException IOException
     */
    public static Boolean setClientId(final QueueConnection conn, long timeout,
            TimeUnit unit) throws LogCollectionException, IOException
    {
        final BlockingQueue<Object> mailbox = new ArrayBlockingQueue<Object>(1);
        ExecutorService executor = Executors.newSingleThreadExecutor(new DaemonThreadFactory());
        executor.submit(new Runnable()
        {
            public void run()
            {
                try
                {
                   
                    conn.setClientID(UUID.randomUUID().toString());
                    mailbox.offer(Boolean.TRUE);
                }
                catch (JMSException e)
                {
                    mailbox.offer(e);
                }
            }
        });
        Object result;
        try
        {
            result = mailbox.poll(timeout, unit);
            if (result == null)
            {
                if (!mailbox.offer("time out"))
                {
                    result = mailbox.take();
                }
            }
        }
        catch (InterruptedException e)
        {
            closeConn(conn);
            throw initCause(new InterruptedIOException(e.getMessage()), e);
        }
        finally
        {
            executor.shutdownNow();
        }
        if (result == null)
        {
            closeConn(conn);
            throw new SocketTimeoutException("Connect timed out");
        }
        if (result instanceof Boolean)
        {
            return (Boolean)result;
        }
        if (result instanceof JMSException)
        {
            closeConn(conn);
            throw new LogCollectionException("IO Execption",
                    (JMSException)result);
        }
        throw new IOException("Unknown reason!");
    }
   
    /**
     * wrapper cause.
     * @param <T>  throwable
     * @param wrapper cause wrapper
     * @param wrapped throwable
     * @return
     */
    private static <T extends Throwable> T initCause(T wrapper,
            Throwable wrapped)
    {
        wrapper.initCause(wrapped);
        return wrapper;
    }
   
    /**
     * close connection
     *
     * @param conn jms connection
     */
    private static void closeConn(Connection conn)
    {
        if (conn != null)
        {
            try
            {
                conn.close();
            }
            catch (JMSException e)
            {
                LOGGER.error(e.toString(), e);
            }
        }
    }
}

/**
* 内部私有类
* 线程工厂，ExecutorService调用newThread方法自动创建线程。
* @version [版本号,YYYY-MM-DD]
* @see [相关类/方法]
* @since [产品/模块版本]
*/
class DaemonThreadFactory implements ThreadFactory
{
    public Thread newThread(Runnable r)
    {
        Thread t = Executors.defaultThreadFactory().newThread(r);
        t.setDaemon(true);
        return t;
    }
}