| /* |
| * Copyright (c) 2007, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| /* |
| * @test |
| * @bug 4405807 |
| * @run main/othervm -Xms10m ReferencesTest |
| * @summary Verify that references from ResourceBundle cache don't prevent |
| * class loader reclamation. |
| */ |
| |
| import java.io.File; |
| import java.lang.ref.WeakReference; |
| import java.lang.reflect.Field; |
| import java.net.URL; |
| import java.net.URLClassLoader; |
| import java.util.Locale; |
| import java.util.Map; |
| import java.util.MissingResourceException; |
| import java.util.ResourceBundle; |
| |
| /** |
| * This test relies on the current behavior of the garbage collector and is |
| * therefore no clear indicator of whether the fix for 4405807 works. |
| * If the test fails, it might indicate a regression, or it might just mean |
| * that a less aggressive garbage collector is used. |
| */ |
| public class ReferencesTest { |
| |
| private static final int CLASS_LOADER_COUNT = 20; |
| |
| // These two parallel arrays have references to the same class loaders. |
| // The weakLoaders array lets us track whether class loaders are being |
| // reclaimed after the references in the loaders array are nulled out. |
| private static ClassLoader[] loaders = new ClassLoader[CLASS_LOADER_COUNT]; |
| private static WeakReference[] weakLoaders = new WeakReference[CLASS_LOADER_COUNT]; |
| |
| public static void main(String[] args) throws Exception { |
| |
| URL testDirectory = new File(System.getProperty("test.classes", ".")).toURL(); |
| |
| for (int i = 0; i < loaders.length; i++) { |
| URL[] urls = { testDirectory }; |
| loaders[i] = new URLClassLoader(urls); |
| weakLoaders[i] = new WeakReference(loaders[i]); |
| } |
| |
| // fill the ResourceBundle cache with entries for half the class loaders |
| loadBundles(0, CLASS_LOADER_COUNT / 2); |
| |
| report("After loading resource bundles for first half of class loaders: "); |
| |
| // release the first half of the class loaders |
| for (int i = 0; i < CLASS_LOADER_COUNT / 2; i++) { |
| loaders[i] = null; |
| } |
| |
| System.gc(); |
| |
| report("After releasing first half of class loaders: "); |
| |
| // fill the ResourceBundle cache with entries for second half the class loaders |
| loadBundles(CLASS_LOADER_COUNT / 2, CLASS_LOADER_COUNT); |
| |
| report("After loading resource bundles for second half of class loaders: "); |
| |
| // release the second half of the class loaders |
| for (int i = CLASS_LOADER_COUNT / 2; i < CLASS_LOADER_COUNT; i++) { |
| loaders[i] = null; |
| } |
| |
| System.gc(); |
| |
| report("After releasing second half of class loaders: "); |
| |
| // The garbage collector in Tiger actually has reclaimed all class |
| // loaders at this point, but in order not to become too dependent |
| // on the current behavior, we only require that the first half |
| // has been reclaimed. |
| if (countLoaders(0, CLASS_LOADER_COUNT / 2) > 0) { |
| throw new RuntimeException("Too many class loaders not reclaimed yet."); |
| } |
| } |
| |
| private static void report(String when) throws Exception { |
| int first = countLoaders(0, CLASS_LOADER_COUNT / 2); |
| int second = countLoaders(CLASS_LOADER_COUNT / 2, CLASS_LOADER_COUNT); |
| |
| Class clazz = ResourceBundle.class; |
| Field cacheList = clazz.getDeclaredField("cacheList"); |
| cacheList.setAccessible(true); |
| int cacheSize = ((Map)cacheList.get(clazz)).size(); |
| |
| System.out.println(when); |
| System.out.println(" " + first + " loaders alive in first half"); |
| System.out.println(" " + second + " loaders alive in second half"); |
| System.out.println(" " + cacheSize + " entries in resource bundle cache"); |
| } |
| |
| private static void loadBundles(int start, int end) throws Exception { |
| for (int i = start; i < end; i++) { |
| // There's no resource bundle for NonExistantBundle - this |
| // let's us test the case where a resource bundle is not found, |
| // which in the past created a SoftReference on the value side |
| // of the cache. |
| try { |
| ResourceBundle.getBundle("NonExistantBundle", Locale.US, loaders[i]); |
| } catch (MissingResourceException e) { |
| } |
| // There's a base resource bundle for ReferencesTestBundle - the |
| // normal case. |
| ResourceBundle.getBundle("ReferencesTestBundle", Locale.US, loaders[i]); |
| } |
| } |
| |
| private static int countLoaders(int start, int end) { |
| int count = 0; |
| for (int i = start; i < end; i++) { |
| if (weakLoaders[i].get() != null) { |
| count++; |
| } |
| } |
| return count; |
| } |
| } |