Java tutorial
/* * Copyright 2013-2014 Amazon.com, Inc. or its affiliates. All Rights Reserved. * * Licensed under the Apache License, Version 2.0 (the "License"). * You may not use this file except in compliance with the License. * A copy of the License is located at * * http://aws.amazon.com/apache2.0 * * or in the "license" file accompanying this file. This file is distributed * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either * express or implied. See the License for the specific language governing * permissions and limitations under the License. */ package com.amazonaws.client.metrics.jmx; import java.lang.management.ManagementFactory; import java.util.List; import javax.management.InstanceAlreadyExistsException; import javax.management.InstanceNotFoundException; import javax.management.MBeanRegistrationException; import javax.management.MBeanServer; import javax.management.MBeanServerFactory; import javax.management.MalformedObjectNameException; import javax.management.NotCompliantMBeanException; import javax.management.ObjectName; import org.apache.commons.logging.LogFactory; /** * MBean related utilities. */ public enum MBeans { ; /** * Registers the given MBean under the given object name to the first * registered MBean server, or the platform MBean server if there is no * explicitly registered MBean server. * * @return true if the registration succeeded, or false if an MBean already * exists under the given object name. * @throws MBeanRegistrationException * The preRegister (MBeanRegistration interface) method of the * MBean has thrown an exception. The MBean will not be * registered. */ public static <T> boolean registerMBean(String objectName, T mbean) throws MBeanRegistrationException { MBeanServer server = getMBeanServer(); try { server.registerMBean(mbean, new ObjectName(objectName)); } catch (MalformedObjectNameException e) { throw new IllegalArgumentException(e); } catch (NotCompliantMBeanException e) { throw new IllegalArgumentException(e); } catch (InstanceAlreadyExistsException e) { LogFactory.getLog(MBeans.class).debug("Failed to register mbean " + objectName, e); return false; } return true; } /** * Unregisters the MBean under the given object name to the first MBean * server, or the platform MBean server if there is no explicitly registered * MBean server. * * @return true if the unregistration succeeded, or false if the MBean * doesn't exist under the given object name. * @throws MBeanRegistrationException * Wraps exceptions thrown by the preRegister(), preDeregister() * methods of the MBeanRegistration interface. */ public static <T> boolean unregisterMBean(String objectName) throws MBeanRegistrationException { MBeanServer server = getMBeanServer(); try { server.unregisterMBean(new ObjectName(objectName)); } catch (MalformedObjectNameException e) { throw new IllegalArgumentException(e); } catch (InstanceNotFoundException e) { LogFactory.getLog(MBeans.class).debug("Failed to unregister mbean " + objectName, e); return false; } return true; } /** * Returns true if an MBean identified by the specified object name is * already registered with the first MBean server, or the platform MBean * server if there is no explicitly registered MBean server; false * otherwise. */ public static boolean isRegistered(String objectName) { MBeanServer server = getMBeanServer(); try { return server.isRegistered(new ObjectName(objectName)); } catch (MalformedObjectNameException e) { throw new IllegalArgumentException(e); } } /** * Returns the first registered MBean server, or the platform MBean server * if there is none. */ public static MBeanServer getMBeanServer() { List<MBeanServer> servers = MBeanServerFactory.findMBeanServer(null); MBeanServer server = servers.size() > 0 ? servers.get(0) : ManagementFactory.getPlatformMBeanServer(); return server; } }