001 /**
002 * GRANITE DATA SERVICES
003 * Copyright (C) 2006-2013 GRANITE DATA SERVICES S.A.S.
004 *
005 * This file is part of the Granite Data Services Platform.
006 *
007 * Granite Data Services is free software; you can redistribute it and/or
008 * modify it under the terms of the GNU Lesser General Public
009 * License as published by the Free Software Foundation; either
010 * version 2.1 of the License, or (at your option) any later version.
011 *
012 * Granite Data Services is distributed in the hope that it will be useful,
013 * but WITHOUT ANY WARRANTY; without even the implied warranty of
014 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser
015 * General Public License for more details.
016 *
017 * You should have received a copy of the GNU Lesser General Public
018 * License along with this library; if not, write to the Free Software
019 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
020 * USA, or see <http://www.gnu.org/licenses/>.
021 */
022 package org.granite.jmx;
023
024 import java.lang.management.ManagementFactory;
025
026 import javax.management.InstanceAlreadyExistsException;
027 import javax.management.InstanceNotFoundException;
028 import javax.management.MBeanRegistrationException;
029 import javax.management.MBeanServer;
030 import javax.management.MBeanServerFactory;
031 import javax.management.NotCompliantMBeanException;
032 import javax.management.ObjectName;
033
034 /**
035 * Utility class for MBean server lookup (with a specific support for the
036 * JBoss JMX console) and MBeans registration.
037 *
038 * @author Franck WOLFF
039 */
040 public class MBeanServerLocator {
041
042 private static MBeanServerLocator instance = null;
043
044 private final MBeanServer server;
045
046 private MBeanServerLocator() {
047 this.server = findMBeanServer();
048 }
049
050 private static MBeanServer findMBeanServer() {
051
052 // Initialize with default platform MBeanServer: must be called first
053 // otherwise jconsole don't work...
054 MBeanServer server = ManagementFactory.getPlatformMBeanServer();
055
056 // Try to find main JBoss MBeanServer.
057 for (Object found : MBeanServerFactory.findMBeanServer(null)) {
058 if (found instanceof MBeanServer && "jboss".equals(((MBeanServer)found).getDefaultDomain())) {
059 server = (MBeanServer)found;
060 break;
061 }
062 }
063
064 return server;
065 }
066
067 /**
068 * Returns a singleton instance of the <tt>MBeanServerLocator</tt> class. The first call
069 * to this method performs an initial lookup of a {@link MBeanServer}.
070 *
071 * @return a singleton instance of the MBeanServerLocator class.
072 */
073 public static synchronized MBeanServerLocator getInstance() {
074 if (instance == null)
075 instance = new MBeanServerLocator();
076 return instance;
077 }
078
079 /**
080 * Returns the {@link MBeanServer} wrapped by this <tt>MBeanServerLocator</tt> instance.
081 *
082 * @return the wrapped {@link MBeanServer}.
083 */
084 public MBeanServer getMBeanServer() {
085 return server;
086 }
087
088 /**
089 * Register the <tt>mbean</tt> object with the supplied <tt>name</tt>. Calling this method is
090 * equivalent to calling {@link #register(Object, ObjectName, boolean)} with its
091 * last parameter set to <tt>false</tt>.
092 *
093 * @param mbean the mbean to register.
094 * @param name the name used for registration.
095 * @throws MBeanRegistrationException rethrown from the wrapped {@link MBeanServer}
096 * @throws InstanceNotFoundException rethrown from the wrapped {@link MBeanServer}
097 * @throws InstanceAlreadyExistsException rethrown from the wrapped {@link MBeanServer}
098 * @throws NotCompliantMBeanException rethrown from the wrapped {@link MBeanServer}
099 */
100 public void register(Object mbean, ObjectName name)
101 throws MBeanRegistrationException, InstanceNotFoundException,
102 InstanceAlreadyExistsException, NotCompliantMBeanException {
103
104 register(mbean, name, false);
105 }
106
107 /**
108 * Register the <tt>mbean</tt> object with the supplied <tt>name</tt>. If the
109 * <tt>replace</tt> parameter is set to true and if a MBean is already registered
110 * under the same name, it is first unregistered.
111 *
112 * @param mbean the mbean to register.
113 * @param name the name used for registration.
114 * @param replace if true, a mbean registered under the same name will be first
115 * unregistered.
116 * @throws MBeanRegistrationException rethrown from the wrapped {@link MBeanServer}
117 * @throws InstanceNotFoundException rethrown from the wrapped {@link MBeanServer}
118 * @throws InstanceAlreadyExistsException rethrown from the wrapped {@link MBeanServer}
119 * @throws NotCompliantMBeanException rethrown from the wrapped {@link MBeanServer}
120 */
121 public void register(Object mbean, ObjectName name, boolean replace)
122 throws MBeanRegistrationException, InstanceNotFoundException,
123 InstanceAlreadyExistsException, NotCompliantMBeanException {
124
125 if (server != null) {
126 if (replace && server.isRegistered(name))
127 server.unregisterMBean(name);
128 server.registerMBean(mbean, name);
129 }
130 }
131
132 /**
133 * Returns <tt>true</tt> if a MBean is registered under the supplied <tt>name</tt>.
134 *
135 * @param name the name to test for registration.
136 * @return true if a mbean is registered, false otherwise.
137 */
138 public boolean isRegistered(ObjectName name) {
139 return server != null && server.isRegistered(name);
140 }
141
142 /**
143 * Unregister any mbean registered under the supplied <tt>name</tt>.
144 *
145 * @param name the name of mbean to unregister.
146 * @throws InstanceNotFoundException rethrown from the wrapped {@link MBeanServer}
147 * @throws MBeanRegistrationException rethrown from the wrapped {@link MBeanServer}
148 */
149 public void unregister(ObjectName name)
150 throws InstanceNotFoundException, MBeanRegistrationException {
151
152 if (server != null)
153 server.unregisterMBean(name);
154 }
155 }