11d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert/* 21d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * Copyright (C) 2005 The Guava Authors 31d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * 41d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * Licensed under the Apache License, Version 2.0 (the "License"); 51d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * you may not use this file except in compliance with the License. 61d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * You may obtain a copy of the License at 71d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * 81d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * http://www.apache.org/licenses/LICENSE-2.0 91d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * 101d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * Unless required by applicable law or agreed to in writing, software 111d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * distributed under the License is distributed on an "AS IS" BASIS, 121d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 131d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * See the License for the specific language governing permissions and 141d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * limitations under the License. 151d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert */ 161d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 171d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringertpackage com.google.common.base; 181d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 191d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringertimport com.google.common.base.internal.Finalizer; 201d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 211d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringertimport junit.framework.TestCase; 221d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 231d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringertimport java.lang.ref.ReferenceQueue; 241d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringertimport java.lang.ref.WeakReference; 251d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringertimport java.net.URL; 261d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringertimport java.net.URLClassLoader; 271d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 281d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert/** 291d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * Unit test for {@link FinalizableReferenceQueue}. 301d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * 311d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * @author Bob Lee 321d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert */ 331d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringertpublic class FinalizableReferenceQueueTest extends TestCase { 341d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 351d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert private FinalizableReferenceQueue frq; 361d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 371d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override 381d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert protected void tearDown() throws Exception { 391d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert frq = null; 401d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 411d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 421d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert public void testFinalizeReferentCalled() { 431d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert MockReference reference = new MockReference( 441d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert frq = new FinalizableReferenceQueue()); 451d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert // wait up to 5s 461d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert for (int i = 0; i < 500; i++) { 471d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert if (reference.finalizeReferentCalled) { 481d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert return; 491d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 501d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert try { 511d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert System.gc(); 521d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert Thread.sleep(10); 531d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } catch (InterruptedException e) { /* ignore */ } 541d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 551d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert fail(); 561d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 571d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 581d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert static class MockReference extends FinalizableWeakReference<Object> { 591d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 601d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert volatile boolean finalizeReferentCalled; 611d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 621d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert MockReference(FinalizableReferenceQueue frq) { 631d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert super(new Object(), frq); 641d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 651d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 661d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override 671d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert public void finalizeReferent() { 681d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert finalizeReferentCalled = true; 691d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 701d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 711d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 721d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert /** 731d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * Keeps a weak reference to the underlying reference queue. When this 741d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * reference is cleared, we know that the background thread has stopped 751d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * and released its strong reference. 761d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert */ 771d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert private WeakReference<ReferenceQueue<Object>> queueReference; 781d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 791d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert public void testThatFinalizerStops() { 801d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert weaklyReferenceQueue(); 811d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 821d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert // wait up to 5s 831d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert for (int i = 0; i < 500; i++) { 841d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert if (queueReference.get() == null) { 851d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert return; 861d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 871d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert try { 881d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert System.gc(); 891d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert Thread.sleep(10); 901d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } catch (InterruptedException e) { /* ignore */ } 911d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 921d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert fail(); 931d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 941d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 951d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert /** 961d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * If we don't keep a strong reference to the reference object, it won't 971d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * be enqueued. 981d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert */ 991d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert FinalizableWeakReference<Object> reference; 1001d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 1011d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert /** 1021d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * Create the FRQ in a method that goes out of scope so that we're sure 1031d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * it will be reclaimed. 1041d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert */ 1051d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert private void weaklyReferenceQueue() { 1061d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert frq = new FinalizableReferenceQueue(); 1071d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert queueReference = new WeakReference<ReferenceQueue<Object>>(frq.queue); 1081d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 1091d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert /* 1101d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * Queue and clear a reference for good measure. We test later on that 1111d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * the finalizer thread stopped, but we should test that it actually 1121d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * started first. 1131d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert */ 1141d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert reference = new FinalizableWeakReference<Object>(new Object(), frq) { 1151d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override 1161d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert public void finalizeReferent() { 1171d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert reference = null; 1181d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert frq = null; 1191d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 1201d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert }; 1211d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 1221d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 1231d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert public void testDecoupledLoader() { 1241d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert FinalizableReferenceQueue.DecoupledLoader decoupledLoader = 1251d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert new FinalizableReferenceQueue.DecoupledLoader() { 1261d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override 1271d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert URLClassLoader newLoader(URL base) { 1281d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert return new DecoupledClassLoader(new URL[] { base }); 1291d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 1301d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert }; 1311d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 1321d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert Class<?> finalizerCopy = decoupledLoader.loadFinalizer(); 1331d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 1341d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert assertNotNull(finalizerCopy); 1351d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert assertNotSame(Finalizer.class, finalizerCopy); 1361d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 1371d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert assertNotNull(FinalizableReferenceQueue.getStartFinalizer(finalizerCopy)); 1381d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 1391d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 1401d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert static class DecoupledClassLoader extends URLClassLoader { 1411d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 1421d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert public DecoupledClassLoader(URL[] urls) { 1431d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert super(urls); 1441d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 1451d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 1461d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override 1471d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert protected synchronized Class<?> loadClass(String name, boolean resolve) 1481d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert throws ClassNotFoundException { 1491d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert // Force Finalizer to load from this class loader, not its parent. 1501d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert if (name.equals(Finalizer.class.getName())) { 1511d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert Class<?> clazz = findClass(name); 1521d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert if (resolve) { 1531d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert resolveClass(clazz); 1541d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 1551d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert return clazz; 1561d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 1571d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 1581d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert return super.loadClass(name, resolve); 1591d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 1601d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 1611d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 1621d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert public void testGetFinalizerUrl() { 1631d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert assertNotNull(getClass().getResource("internal/Finalizer.class")); 1641d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 1651d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert} 166