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    <blockquote> <p>1) When would someone called the cancel method with the mayInterruptIfRunning parameter set to false and what would it mean?</p> </blockquote> <p>When you <strong>attempt</strong> to <a href="http://docs.oracle.com/javase/7/docs/api/java/util/concurrent/Future.html#cancel%28boolean%29" rel="nofollow">cancel</a> an asynchronous invocation, you are not sure what the exactly status of the server side method is. The method maybe is still waiting for execution, maybe it was executed or it has already started.</p> <p>The parameter <code>mayInterruptIfRunning</code> is useful for the last case. However, it only makes sense if you have implemented some special logic in the server side, I mean, if you check the status of <code>SessionContext.wasCanceled()</code> method. </p> <p>Just an example:</p> <pre><code>//code that execuete in the asynchronus service while (myCondition) { doSomething(); if (mySessionCtx.wasCancelCalled()) break; } </code></pre> <p>If the method is executing, and you call <code>cancel()</code> with <code>mayInterruptIfRunning = false</code>, the loop won´t finalice until myCondition is false. If the parameter is true, the while loop will be interrupted.</p> <p>Notice that for the <a href="https://java.net/projects/ejb-spec/lists/jsr345-experts/archive/2013-03/message/48" rel="nofollow">moment</a> <code>cancel()</code> doesn´t interrupt the Thread execution.</p> <blockquote> <p>2) What is the difference in results coming from the methods SessionContext.wasCancelled() and Future.isCancelled()?</p> </blockquote> <p>As described above, <code>SessionContext.wasCancelled()</code> is used in the server side whereas that <code>Future&lt;V&gt;.isCancelled()</code> is used in the client side to determine if the task was cancelled.</p>
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    1. POCancelling an Asynchronous Method Invocation
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    1. USGabriel Aramburu
    1. USGabriel Aramburu
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    1. COCan you explain further how does it work: " with mayInterruptIfRunning = false, the loop won´t finalize until myCondition is true" ? If you mean "until myCondition is false", then the cancelation is never performed, so what the purpose of calling it with mayInterruptIfRunning = false ?
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      1. USarjacsoh
    2. COyes, I mean "until myCondition is false" sorry;and yes, if the method is running the cancelation is never performed; The purpose is to cancel the asynchronous call if it is not already executing. I agree with you that the vast majority of the time, cancel() will be called with true, but imagine that under certain condition (imposed for your business requirements) the client code can decide if to interrupt the method execution is suitable or not.
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      1. USGabriel Aramburu
 

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