1 /* 2 * Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 */ 23 24 /* 25 * @test 26 * @bug 8164512 27 * @summary verify if the native library is unloaded when the class loader is GC'ed 28 * @build p.Test 29 * @run main/othervm/native -Xcheck:jni NativeLibraryTest 30 */ 31 32 import java.io.IOException; 33 import java.net.MalformedURLException; 34 import java.net.URL; 35 import java.net.URLClassLoader; 36 import java.nio.file.Files; 37 import java.nio.file.Path; 38 import java.nio.file.Paths; 39 40 public class NativeLibraryTest { 41 static final Path CLASSES = Paths.get("classes"); 42 static int unloadedCount = 0; 43 44 /* 45 * Called by JNI_OnUnload when the native library is unloaded 46 */ 47 static void nativeLibraryUnloaded() { 48 unloadedCount++; 49 } 50 51 public static void main(String... args) throws Exception { 52 setup(); 53 54 for (int count=1; count <= 5; count++) { 55 // create a class loader and load a native library 56 runTest(); 57 // unloading the class loader and native library 58 System.gc(); 59 // give Cleaner thread a chance to unload the native library 60 Thread.sleep(100); 61 62 // unloadedCount is incremented when the native library is unloaded 63 if (count != unloadedCount) { 64 throw new RuntimeException("Expected unloaded=" + count + 65 " but got=" + unloadedCount); 66 } 67 } 68 } 69 70 /* 71 * Loads p.Test class with a new class loader and its static initializer 72 * will load a native library. 73 * 74 * The class loader becomes unreachable when this method returns and 75 * the native library should be unloaded at some point after the class 76 * loader is garbage collected. 77 */ 78 static void runTest() throws Exception { 79 // invoke p.Test.run() that loads the native library 80 Runnable r = newTestRunnable(); 81 r.run(); 82 83 // reload the native library by the same class loader 84 r.run(); 85 86 // load the native library by another class loader 87 Runnable r1 = newTestRunnable(); 88 try { 89 r1.run(); 90 throw new RuntimeException("should fail to load the native library" + 91 " by another class loader"); 92 } catch (UnsatisfiedLinkError e) {} 93 } 94 95 /* 96 * Loads p.Test class with a new class loader and returns 97 * a Runnable instance. 98 */ 99 static Runnable newTestRunnable() throws Exception { 100 TestLoader loader = new TestLoader(); 101 Class<?> c = Class.forName("p.Test", true, loader); 102 return (Runnable) c.newInstance(); 103 } 104 105 static class TestLoader extends URLClassLoader { 106 static URL[] toURLs() { 107 try { 108 return new URL[] { CLASSES.toUri().toURL() }; 109 } catch (MalformedURLException e) { 110 throw new Error(e); 111 } 112 } 113 114 TestLoader() { 115 super("testloader", toURLs(), ClassLoader.getSystemClassLoader()); 116 } 117 } 118 119 /* 120 * move p/Test.class out from classpath to the scratch directory 121 */ 122 static void setup() throws IOException { 123 String dir = System.getProperty("test.classes", "."); 124 Path file = Paths.get("p", "Test.class"); 125 Files.createDirectories(CLASSES.resolve("p")); 126 Files.move(Paths.get(dir).resolve(file), 127 CLASSES.resolve("p").resolve("Test.class")); 128 } 129 }