1 /* 2 * Copyright (c) 2013, 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. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 package jdk.jfr.event.runtime; 27 28 import java.util.List; 29 30 import jdk.jfr.Recording; 31 import jdk.jfr.consumer.RecordedEvent; 32 import jdk.test.lib.Asserts; 33 import jdk.test.lib.jfr.EventNames; 34 import jdk.test.lib.jfr.Events; 35 import jdk.test.lib.jfr.TestClassLoader; 36 37 /** 38 * @test 39 * @key jfr 40 * @requires vm.hasJFR 41 * @library /test/lib /test/jdk 42 * @build jdk.jfr.event.runtime.TestClasses 43 * @run main/othervm jdk.jfr.event.runtime.TestClassLoadingStatisticsEvent 44 */ 45 /** 46 * This test will load a number of classes. After each load step we verify that 47 * the loadedClassCount and unloadedClassCount attributes are correct. 48 * 49 * System.gc() will trigger class unloading if -XX:+ExplicitGCInvokesConcurrent 50 * is NOT set. If this flag is set G1 will never unload classes on System.gc() 51 * and CMS will not guarantee that all semantically dead classes will be 52 * unloaded. As far as the "jfr" key guarantees no VM flags are set from the 53 * outside it should be enough with System.gc(). 54 */ 55 public class TestClassLoadingStatisticsEvent { 56 57 private final static String EVENT_PATH = EventNames.ClassLoadingStatistics; 58 private final static String TESTCLASS_PUBLIC_STATIC = 59 "jdk.jfr.event.runtime.TestClasses$TestClassPublicStatic"; 60 private final static String TESTCLASS_PUBLIC_STATIC_INNER = 61 "jdk.jfr.event.runtime.TestClasses$TestClassPublicStatic$TestClassPublicStaticInner"; 62 63 // Declare unloadableClassLoader as "public static" 64 // to prevent the compiler to optimize away all unread writes 65 public static TestClassLoader unloadableClassLoader; 66 67 public static void main(String[] args) throws Throwable { 68 // Load twice to get more stable result. 69 RecordedEvent event = getCurrentEvent(); 70 event = getCurrentEvent(); 71 72 // Declare class ClassLoadingStatisticsHelper. 73 TestClasses[] helpers = new TestClasses[10]; 74 event = verifyCountDelta(event, 1, 0); 75 76 // Should load classes TestClassPrivate and TestClassPrivateStatic. 77 for (int c = 0; c < helpers.length; c++) { 78 helpers[c] = new TestClasses(); 79 } 80 event = verifyCountDelta(event, 2, 0); 81 82 // Load classes TestClassProtected and B2. 83 helpers[0].new TestClassProtected(); 84 helpers[1].new TestClassProtected(); // This class is already loaded. 85 new TestClasses.TestClassProtectedStatic(); 86 event = verifyCountDelta(event, 2, 0); 87 88 // Load classes TestClassProtected1 and TestClassProtectedStatic1. 89 for (int c = 0; c < helpers.length; c++) { 90 helpers[c].loadClasses(); 91 } 92 event = verifyCountDelta(event, 2, 0); 93 94 // Load the classes with separate class loader. Will be unloaded later. 95 unloadableClassLoader = new TestClassLoader(); 96 97 unloadableClassLoader.loadClass(TESTCLASS_PUBLIC_STATIC_INNER); 98 event = verifyCountDelta(event, 1, 0); 99 100 unloadableClassLoader.loadClass(TESTCLASS_PUBLIC_STATIC); 101 event = verifyCountDelta(event, 1, 0); 102 103 // This System.gc() should not unload classes, since the 104 // unloadableClassLoader object is still active. 105 System.gc(); 106 event = verifyCountDelta(event, 0, 0); 107 108 // make classes are unloaded. 109 unloadableClassLoader = null; 110 System.gc(); 111 event = verifyCountDelta(event, 0, 2); 112 } 113 114 private static RecordedEvent getCurrentEvent() throws Throwable { 115 Recording recording = new Recording(); 116 recording.enable(EVENT_PATH); 117 recording.start(); 118 recording.stop(); 119 List<RecordedEvent> events = Events.fromRecording(recording); 120 Asserts.assertFalse(events.isEmpty(), "No events in recording"); 121 RecordedEvent event = events.get(0); 122 return event; 123 } 124 125 private static RecordedEvent verifyCountDelta( 126 RecordedEvent prevEvent, int loadDelta, int unloadDelta) throws Throwable { 127 RecordedEvent currEvent = null; 128 try { 129 long prevLoad = Events.assertField(prevEvent, "loadedClassCount").getValue(); 130 long prevUnload = Events.assertField(prevEvent, "unloadedClassCount").getValue(); 131 132 currEvent = getCurrentEvent(); 133 Events.assertField(currEvent, "loadedClassCount").atLeast(prevLoad + loadDelta); 134 Events.assertField(currEvent, "unloadedClassCount").atLeast(prevUnload + unloadDelta); 135 return currEvent; 136 } catch (Throwable t) { 137 System.out.println("verifyCountDelta failed. prevEvent=" + prevEvent + ", currEvent=" + currEvent); 138 throw t; 139 } 140 } 141 142 }