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    <p>This sounds to me that you are not doing proper exception handling. You say "thread silently dies off" but that doesn't happen in Java. I would audit your exceptions and watch for the following problems:</p> <ul> <li>Watch out for <code>throws Exception</code> on a method. This hides all sorts of evils. A method should usually enumerate the exceptions that it throws.</li> <li>If an Exception throws too many different types of exceptions then that is a signal that it is too large. Consider splitting it into multiple smaller methods. Or handle the specific exceptions inside of the method and throw one exception out.</li> <li>Try to have small try/catch blocks which catch a single exception if possible. Don't inclose huge blocks of code with <code>try { ... } catch (Exception e) { ... }</code>. That, again, hides evils.</li> <li>If you catch an exception, make sure you aren't just blindly continuing. If this is a background thread then maybe it should exit or restart the socket or...</li> <li>Make sure you are properly reporting <em>all</em> exceptions. Every catch block should do something with the exception. <code>e.printStackTrace()</code> may work but providing more information about the problem is usually in order.</li> </ul> <blockquote> <p>But I don't know how to re-start a stopped thread.</p> </blockquote> <p>You do not re-start a stopped thread, you start another one. If the thread should not be shutting down at all then it needs to re-open a socket or maybe re-start its <code>RabbitMQ</code> connection. Again, it's about proper exception handling. I don't know <code>RabbitMQ</code> but something like the following pseudo code might help:</p> <pre><code>public void run() { while (!shutdown) { Connection conn = null; try { conn = rabbitMq.start(); processQueue(conn); } catch (IOException e) { // TODO: log the exception here } finally { // make sure we close the connection if (conn != null) { conn.close(); } } try { // we sleep here to not spin if the RabbitMQ host goes down Thread.sleep(1000); } catch (InterruptedException e) { Thread.currentThread.interrupt(); // bail if someone interrupts us return; } } </code></pre> <p>Best of luck.</p>
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    1. POHow to gain a lost connection to server without restarting the Server, when a listener thread dies
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    1. POHow to gain a lost connection to server without restarting the Server, when a listener thread dies
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    1. COThanks a lot Gray.. I could resolve the problem now . I was in impression that as soon as thread gets an exception it goes to catch block and then the thread is claimed by JVM. Which obviously not the case as per your answer.
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      1. USAnupam Gupta
    2. COwhat I have understood from your answer is "even if exception occurs then also the thread is alive (provided exception is handled properly), and it will keep trying to get back connection, once it gets the connection it will do its normal things" .....Kindly confirm my understanding is correct
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    3. COYes, exactly right @Anupam. Exception handling does not mean that anything is killed. Only if the end of the `run()` method is reached does the thread go away -- it is never silently. Remember also that the main thread is the same way.
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