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/* |
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* Written by Martin Buchholz and Jason Mehrens with assistance from |
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* members of JCP JSR-166 Expert Group and released to the public |
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* domain, as explained at |
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* http://creativecommons.org/publicdomain/zero/1.0/ |
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*/ |
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|
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/* |
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* @test |
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* @summary Only one thread should be created when a thread needs to |
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* be kept alive to service a delayed task waiting in the queue. |
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* @library /lib/testlibrary/ |
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*/ |
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|
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import static java.util.concurrent.TimeUnit.MILLISECONDS; |
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|
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import java.util.concurrent.ScheduledThreadPoolExecutor; |
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import java.util.concurrent.ThreadFactory; |
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import java.util.concurrent.atomic.AtomicLong; |
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import jdk.testlibrary.Utils; |
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|
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public class ThreadRestarts { |
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static final long LONG_DELAY_MS = Utils.adjustTimeout(10_000); |
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static final long FAR_FUTURE_MS = 10 * LONG_DELAY_MS; |
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|
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public static void main(String[] args) throws Exception { |
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test(false); |
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test(true); |
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} |
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|
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private static void test(boolean allowTimeout) throws Exception { |
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CountingThreadFactory ctf = new CountingThreadFactory(); |
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ScheduledThreadPoolExecutor stpe |
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= new ScheduledThreadPoolExecutor(10, ctf); |
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try { |
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// schedule a dummy task in the "far future" |
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Runnable nop = new Runnable() { public void run() {}}; |
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stpe.schedule(nop, FAR_FUTURE_MS, MILLISECONDS); |
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stpe.setKeepAliveTime(1L, MILLISECONDS); |
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stpe.allowCoreThreadTimeOut(allowTimeout); |
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MILLISECONDS.sleep(12L); |
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} finally { |
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stpe.shutdownNow(); |
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if (!stpe.awaitTermination(LONG_DELAY_MS, MILLISECONDS)) |
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throw new AssertionError("timed out"); |
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} |
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if (ctf.count.get() > 1) |
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throw new AssertionError( |
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String.format("%d threads created, 1 expected", |
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ctf.count.get())); |
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} |
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|
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static class CountingThreadFactory implements ThreadFactory { |
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final AtomicLong count = new AtomicLong(0L); |
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|
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public Thread newThread(Runnable r) { |
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count.getAndIncrement(); |
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Thread t = new Thread(r); |
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t.setDaemon(true); |
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return t; |
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} |
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} |
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} |
