1 /* 2 * Copyright (c) 2003, 2008, 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 java.lang.management; 27 28 /** 29 * The management interface for the class loading system of 30 * the Java virtual machine. 31 * 32 * <p> A Java virtual machine has a single instance of the implementation 33 * class of this interface. This instance implementing this interface is 34 * an <a href="ManagementFactory.html#MXBean">MXBean</a> 35 * that can be obtained by calling 36 * the {@link ManagementFactory#getClassLoadingMXBean} method or 37 * from the {@link ManagementFactory#getPlatformMBeanServer 38 * platform <tt>MBeanServer</tt>}. 39 * 40 * <p>The <tt>ObjectName</tt> for uniquely identifying the MXBean for 41 * the class loading system within an <tt>MBeanServer</tt> is: 42 * <blockquote> 43 * {@link ManagementFactory#CLASS_LOADING_MXBEAN_NAME 44 * <tt>java.lang:type=ClassLoading</tt>} 45 * </blockquote> 46 * 47 * It can be obtained by calling the 48 * {@link PlatformManagedObject#getObjectName} method. 49 * 50 * @see ManagementFactory#getPlatformMXBeans(Class) 51 * @see <a href="../../../javax/management/package-summary.html"> 52 * JMX Specification.</a> 53 * @see <a href="package-summary.html#examples"> 54 * Ways to Access MXBeans</a> 55 * 56 * @author Mandy Chung 57 * @since 1.5 58 */ 59 public interface ClassLoadingMXBean extends PlatformManagedObject { 60 61 /** 62 * Returns the total number of classes that have been loaded since 63 * the Java virtual machine has started execution. 64 * 65 * @return the total number of classes loaded. 66 * 67 */ getTotalLoadedClassCount()68 public long getTotalLoadedClassCount(); 69 70 /** 71 * Returns the number of classes that are currently loaded in the 72 * Java virtual machine. 73 * 74 * @return the number of currently loaded classes. 75 */ getLoadedClassCount()76 public int getLoadedClassCount(); 77 78 /** 79 * Returns the total number of classes unloaded since the Java virtual machine 80 * has started execution. 81 * 82 * @return the total number of unloaded classes. 83 */ getUnloadedClassCount()84 public long getUnloadedClassCount(); 85 86 /** 87 * Tests if the verbose output for the class loading system is enabled. 88 * 89 * @return <tt>true</tt> if the verbose output for the class loading 90 * system is enabled; <tt>false</tt> otherwise. 91 */ isVerbose()92 public boolean isVerbose(); 93 94 /** 95 * Enables or disables the verbose output for the class loading 96 * system. The verbose output information and the output stream 97 * to which the verbose information is emitted are implementation 98 * dependent. Typically, a Java virtual machine implementation 99 * prints a message each time a class file is loaded. 100 * 101 * <p>This method can be called by multiple threads concurrently. 102 * Each invocation of this method enables or disables the verbose 103 * output globally. 104 * 105 * @param value <tt>true</tt> to enable the verbose output; 106 * <tt>false</tt> to disable. 107 * 108 * @exception java.lang.SecurityException if a security manager 109 * exists and the caller does not have 110 * ManagementPermission("control"). 111 */ setVerbose(boolean value)112 public void setVerbose(boolean value); 113 114 } 115