| 1 |
/* |
| 2 |
* Written by Doug Lea and Martin Buchholz with assistance from |
| 3 |
* members of JCP JSR-166 Expert Group and released to the public |
| 4 |
* domain, as explained at |
| 5 |
* http://creativecommons.org/publicdomain/zero/1.0/ |
| 6 |
*/ |
| 7 |
|
| 8 |
import java.lang.invoke.MethodHandles; |
| 9 |
import java.lang.invoke.VarHandle; |
| 10 |
import java.util.concurrent.CountDownLatch; |
| 11 |
import java.util.concurrent.ForkJoinPool; |
| 12 |
import java.util.concurrent.ForkJoinTask; |
| 13 |
import java.util.concurrent.Future; |
| 14 |
import java.util.stream.Stream; |
| 15 |
|
| 16 |
import junit.framework.Test; |
| 17 |
import junit.framework.TestSuite; |
| 18 |
|
| 19 |
public class ForkJoinPool9Test extends JSR166TestCase { |
| 20 |
public static void main(String[] args) { |
| 21 |
main(suite(), args); |
| 22 |
} |
| 23 |
|
| 24 |
public static Test suite() { |
| 25 |
return new TestSuite(ForkJoinPool9Test.class); |
| 26 |
} |
| 27 |
|
| 28 |
/** |
| 29 |
* Check handling of common pool thread context class loader |
| 30 |
*/ |
| 31 |
@SuppressWarnings("removal") |
| 32 |
public void testCommonPoolThreadContextClassLoader() throws Throwable { |
| 33 |
if (!testImplementationDetails) return; |
| 34 |
|
| 35 |
// Ensure common pool has at least one real thread |
| 36 |
String prop = System.getProperty( |
| 37 |
"java.util.concurrent.ForkJoinPool.common.parallelism"); |
| 38 |
if ("0".equals(prop)) return; |
| 39 |
|
| 40 |
VarHandle CCL = |
| 41 |
MethodHandles.privateLookupIn(Thread.class, MethodHandles.lookup()) |
| 42 |
.findVarHandle(Thread.class, "contextClassLoader", ClassLoader.class); |
| 43 |
ClassLoader systemClassLoader = ClassLoader.getSystemClassLoader(); |
| 44 |
boolean haveSecurityManager = (System.getSecurityManager() != null); |
| 45 |
CountDownLatch runInCommonPoolStarted = new CountDownLatch(1); |
| 46 |
ClassLoader classLoaderDistinctFromSystemClassLoader |
| 47 |
= ClassLoader.getPlatformClassLoader(); |
| 48 |
assertNotSame(classLoaderDistinctFromSystemClassLoader, |
| 49 |
systemClassLoader); |
| 50 |
Runnable runInCommonPool = () -> { |
| 51 |
runInCommonPoolStarted.countDown(); |
| 52 |
assertTrue(ForkJoinTask.inForkJoinPool()); |
| 53 |
assertSame(ForkJoinPool.commonPool(), ForkJoinTask.getPool()); |
| 54 |
Thread currentThread = Thread.currentThread(); |
| 55 |
|
| 56 |
Stream.of(systemClassLoader, null).forEach(cl -> { |
| 57 |
if (randomBoolean()) |
| 58 |
// should always be permitted, without effect |
| 59 |
currentThread.setContextClassLoader(cl); |
| 60 |
}); |
| 61 |
|
| 62 |
Stream.of(currentThread.getContextClassLoader(), |
| 63 |
(ClassLoader) CCL.get(currentThread)) |
| 64 |
.forEach(cl -> assertTrue(cl == systemClassLoader || cl == null)); |
| 65 |
|
| 66 |
if (haveSecurityManager) |
| 67 |
assertThrows( |
| 68 |
SecurityException.class, |
| 69 |
() -> System.getProperty("foo"), |
| 70 |
() -> currentThread.setContextClassLoader( |
| 71 |
classLoaderDistinctFromSystemClassLoader)); |
| 72 |
// TODO ? |
| 73 |
// if (haveSecurityManager |
| 74 |
// && Thread.currentThread().getClass().getSimpleName() |
| 75 |
// .equals("InnocuousForkJoinWorkerThread")) |
| 76 |
// assertThrows(SecurityException.class, /* ?? */); |
| 77 |
}; |
| 78 |
Future<?> f = ForkJoinPool.commonPool().submit(runInCommonPool); |
| 79 |
// Ensure runInCommonPool is truly running in the common pool, |
| 80 |
// by giving this thread no opportunity to "help" on get(). |
| 81 |
await(runInCommonPoolStarted); |
| 82 |
assertNull(f.get()); |
| 83 |
} |
| 84 |
|
| 85 |
} |
