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Thread.join with retry pattern

Having looked at the sample code with help Thread, I often come across this replay pattern.

boolean retry = true;
while (retry) {
    try {
        myThread.join();
        retry = false;
    } catch (InterruptedException e) {
        // Nothing ...
    }
}

join() must wait forever.

If the current thread is interrupted earlier or during joinand thus receives InterruptedException, is it really myThreadjoining?

Is this some leftover cut paste in the pattern?

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2 answers

The other is Threadnot join()yours Threadin the case InterruptedException. join()must wait always or until the call Threadis interrupt()-ed.

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public static void joinThread(final Thread thread) {
    while (true)
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        } catch (final InterruptedException e) {
            Logger.getGlobal().log(Level.ERROR, "Unexpected InterruptedException", e);
        }
}

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public static void joinThread(final Thread thread) {
    try {
        thread.join();
    } catch (final InterruptedException e) {
        Logger.getGlobal().log(Level.ERROR, "Unexpected InterruptedException", e);
    }
}

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public static void joinThread(final Thread thread) {
    try {
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    }
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public static void joinThread(final Thread thread) throws InterruptedException {
    try {
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    }
}

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public static void joinThread(final Thread thread) {
    try {
        thread.join();
    } catch (final InterruptedException e) {
        Logger.getGlobal().log(Level.FINE, "Got InterruptedException, handling it", e);
        // ...whatever...
    }
}

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// Only throws AssertionError if assertions are enabled.
public static void joinThread(final Thread thread) {
    try {
        thread.join();
    } catch (final InterruptedException e) {
        Logger.getGlobal().log(Level.ERROR, "Unexpected InterruptedException", e);
        assert false : e;
    }
}

// Always throws AssertionError.
public static void joinThread(final Thread thread) {
    try {
        thread.join();
    } catch (final InterruptedException e) {
        Logger.getGlobal().log(Level.FATAL, "Unexpected InterruptedException", e);
        throw new AssertionError(e, "Unexpected Thread interruption.");
    }
}

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public static void joinThread(final Thread thread) {
    try {
        thread.join();
    } catch (final InterruptedException e) {
        Logger.getGlobal().log(Level.ERROR, "Unexpected InterruptedException", e);
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    }
}

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+2

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+1

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