1 /*
   2  * Copyright (c) 2016, 2018, 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  * @key gc
  27  * @bug 8114823
  28  * @requires vm.gc == null
  29  * @requires vm.opt.ExplicitGCInvokesConcurrent != true
  30  * @requires vm.opt.ClassUnloading != true
  31  * @library /test/lib
  32  * @modules java.base/jdk.internal.misc
  33  *          java.management
  34  * @build sun.hotspot.WhiteBox
  35  * @run driver ClassFileInstaller sun.hotspot.WhiteBox
  36  *                              sun.hotspot.WhiteBox$WhiteBoxPermission
  37  *
  38  * @run main/othervm -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI
  39  *                   -XX:-ClassUnloading -XX:+UseG1GC TestClassUnloadingDisabled
  40  *
  41  * @run main/othervm -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI
  42  *                   -XX:-ClassUnloading -XX:+UseSerialGC TestClassUnloadingDisabled
  43  *
  44  * @run main/othervm -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI
  45  *                   -XX:-ClassUnloading -XX:+UseParallelGC TestClassUnloadingDisabled
  46  *
  47  */
  48 
  49 /*
  50  * @test
  51  * @key gc
  52  * @bug 8114823
  53  * @comment Graal does not support CMS
  54  * @requires vm.gc=="null" & !vm.graal.enabled
  55  * @requires vm.opt.ExplicitGCInvokesConcurrent != true
  56  * @requires vm.opt.ClassUnloading != true
  57  * @library /test/lib
  58  * @modules java.base/jdk.internal.misc
  59  *          java.management
  60  * @build sun.hotspot.WhiteBox
  61  * @run driver ClassFileInstaller sun.hotspot.WhiteBox
  62  *                              sun.hotspot.WhiteBox$WhiteBoxPermission
  63  * @run main/othervm -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI
  64  *                   -XX:-ClassUnloading -XX:+UseConcMarkSweepGC TestClassUnloadingDisabled
  65  */
  66 
  67 import java.io.File;
  68 import java.io.IOException;
  69 import java.nio.file.Files;
  70 import java.nio.file.Path;
  71 import java.nio.file.Paths;
  72 
  73 import sun.hotspot.WhiteBox;
  74 
  75 import static jdk.test.lib.Asserts.*;
  76 
  77 public class TestClassUnloadingDisabled {
  78     public static void main(String args[]) throws Exception {
  79         final WhiteBox wb = WhiteBox.getWhiteBox();
  80         // Fetch the dir where the test class and the class
  81         // to be loaded resides.
  82         String classDir = TestClassUnloadingDisabled.class.getProtectionDomain().getCodeSource().getLocation().getPath();
  83         String className = "ClassToLoadUnload";
  84 
  85         assertFalse(wb.isClassAlive(className), "Should not be loaded yet");
  86 
  87         // The NoPDClassLoader handles loading classes in the test directory
  88         // and loads them without a protection domain, which in some cases
  89         // keeps the class live regardless of marking state.
  90         NoPDClassLoader nopd = new NoPDClassLoader(classDir);
  91         nopd.loadClass(className);
  92 
  93         assertTrue(wb.isClassAlive(className), "Class should be loaded");
  94 
  95         // Clear the class-loader, class and object references to make
  96         // class unloading possible.
  97         nopd = null;
  98 
  99         System.gc();
 100         assertTrue(wb.isClassAlive(className), "Class should not have ben unloaded");
 101     }
 102 }
 103 
 104 class NoPDClassLoader extends ClassLoader {
 105     String path;
 106 
 107     NoPDClassLoader(String path) {
 108         this.path = path;
 109     }
 110 
 111     public Class<?> loadClass(String name) throws ClassNotFoundException {
 112         byte[] cls = null;
 113         File f = new File(path,name + ".class");
 114 
 115         // Delegate class loading if class not present in the given
 116         // directory.
 117         if (!f.exists()) {
 118             return super.loadClass(name);
 119         }
 120 
 121         try {
 122             Path path = Paths.get(f.getAbsolutePath());
 123             cls = Files.readAllBytes(path);
 124         } catch (IOException e) {
 125             throw new ClassNotFoundException(name);
 126         }
 127 
 128         // Define class with no protection domain and resolve it.
 129         return defineClass(name, cls, 0, cls.length, null);
 130     }
 131 }
 132 
 133 class ClassToLoadUnload {
 134 }