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/* |
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* Written by Doug Lea and Martin Buchholz 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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import java.lang.invoke.MethodHandles; |
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import java.lang.invoke.VarHandle; |
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import java.util.concurrent.CountDownLatch; |
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import java.util.concurrent.ForkJoinPool; |
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import java.util.concurrent.ForkJoinTask; |
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import java.util.concurrent.Future; |
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import java.util.stream.Stream; |
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|
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import junit.framework.Test; |
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import junit.framework.TestSuite; |
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|
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public class ForkJoinPool9Test extends JSR166TestCase { |
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public static void main(String[] args) { |
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main(suite(), args); |
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} |
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|
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public static Test suite() { |
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return new TestSuite(ForkJoinPool9Test.class); |
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} |
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|
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/** |
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* Check handling of common pool thread context class loader |
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*/ |
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public void testCommonPoolThreadContextClassLoader() throws Throwable { |
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if (!testImplementationDetails) return; |
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|
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// Ensure common pool has at least one real thread |
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String prop = System.getProperty( |
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"java.util.concurrent.ForkJoinPool.common.parallelism"); |
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if ("0".equals(prop)) return; |
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|
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VarHandle CCL = |
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MethodHandles.privateLookupIn(Thread.class, MethodHandles.lookup()) |
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.findVarHandle(Thread.class, "contextClassLoader", ClassLoader.class); |
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ClassLoader systemClassLoader = ClassLoader.getSystemClassLoader(); |
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boolean haveSecurityManager = (System.getSecurityManager() != null); |
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CountDownLatch runInCommonPoolStarted = new CountDownLatch(1); |
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ClassLoader classLoaderDistinctFromSystemClassLoader |
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= ClassLoader.getPlatformClassLoader(); |
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assertNotSame(classLoaderDistinctFromSystemClassLoader, |
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systemClassLoader); |
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Runnable runInCommonPool = () -> { |
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runInCommonPoolStarted.countDown(); |
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assertTrue(ForkJoinTask.inForkJoinPool()); |
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assertSame(ForkJoinPool.commonPool(), ForkJoinTask.getPool()); |
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Thread currentThread = Thread.currentThread(); |
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|
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Stream.of(systemClassLoader, null).forEach(cl -> { |
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if (randomBoolean()) |
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// should always be permitted, without effect |
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currentThread.setContextClassLoader(cl); |
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}); |
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|
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Stream.of(currentThread.getContextClassLoader(), |
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(ClassLoader) CCL.get(currentThread)) |
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.forEach(cl -> assertTrue(cl == systemClassLoader || cl == null)); |
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|
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if (haveSecurityManager) |
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assertThrows( |
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SecurityException.class, |
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() -> System.getProperty("foo"), |
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() -> currentThread.setContextClassLoader( |
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classLoaderDistinctFromSystemClassLoader)); |
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// TODO ? |
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// if (haveSecurityManager |
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// && Thread.currentThread().getClass().getSimpleName() |
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// .equals("InnocuousForkJoinWorkerThread")) |
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// assertThrows(SecurityException.class, /* ?? */); |
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}; |
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Future<?> f = ForkJoinPool.commonPool().submit(runInCommonPool); |
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// Ensure runInCommonPool is truly running in the common pool, |
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// by giving this thread no opportunity to "help" on get(). |
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await(runInCommonPoolStarted); |
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assertNull(f.get()); |
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} |
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|
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} |
