Java tutorial
/* * (C) Copyright 2006-2008 Nuxeo SA (http://nuxeo.com/) and others. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License 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. * * Contributors: * matic */ package org.nuxeo.runtime.management; import java.io.IOException; import java.lang.management.ManagementFactory; import java.net.InetAddress; import java.net.MalformedURLException; import java.net.UnknownHostException; import java.rmi.RemoteException; import java.rmi.registry.LocateRegistry; import java.util.HashMap; import java.util.Map; import javax.management.MBeanServer; import javax.management.MBeanServerFactory; import javax.management.ObjectName; import javax.management.remote.JMXServiceURL; import javax.management.remote.rmi.RMIConnectorServer; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.nuxeo.runtime.model.ComponentInstance; import org.nuxeo.runtime.model.DefaultComponent; public class ServerLocatorService extends DefaultComponent implements ServerLocator { public static final String LOCATORS_EXT_KEY = "locators"; private static final Log log = LogFactory.getLog(ServerLocatorService.class); protected final Map<String, MBeanServer> servers = new HashMap<String, MBeanServer>(); protected MBeanServer defaultServer = ManagementFactory.getPlatformMBeanServer(); protected String hostname; @Override public void registerContribution(Object contribution, String extensionPoint, ComponentInstance contributor) { if (extensionPoint.equals(LOCATORS_EXT_KEY)) { doRegisterLocator((ServerLocatorDescriptor) contribution); } } @Override public void unregisterContribution(Object contribution, String extensionPoint, ComponentInstance contributor) { if (extensionPoint.equals(LOCATORS_EXT_KEY)) { doUnregisterLocator((ServerLocatorDescriptor) contribution); } } protected void doRegisterLocator(ServerLocatorDescriptor descriptor) { MBeanServer server = descriptor.isExisting ? doFindServer(descriptor.domainName) : doCreateServer(descriptor); servers.put(descriptor.domainName, server); if (descriptor.isDefault) { defaultServer = server; } } protected String doGetHostname() { if (hostname != null) { return hostname; } try { InetAddress addr = InetAddress.getLocalHost(); hostname = addr.getHostName(); } catch (UnknownHostException e) { hostname = "localhost"; } return hostname; } protected JMXServiceURL doFormatServerURL(ServerLocatorDescriptor descriptor) { try { return new JMXServiceURL("service:jmx:rmi:///jndi/rmi://localhost:" + descriptor.rmiPort + "/" + descriptor.domainName + "/jmxrmi"); } catch (MalformedURLException e) { throw new ManagementRuntimeException("Cannot format url for " + descriptor.domainName); } } protected String doFormatThreadName(ServerLocatorDescriptor descriptor) { return "mbeanServer-" + descriptor.domainName; } protected MBeanServer doCreateServer(final ServerLocatorDescriptor descriptor) { MBeanServer server = MBeanServerFactory.createMBeanServer(); JMXServiceURL url = doFormatServerURL(descriptor); if (!descriptor.remote) { return server; } final RMIConnectorServer connector; try { connector = new RMIConnectorServer(url, null, server); } catch (IOException e) { throw new ManagementRuntimeException("Cannot start connector for " + descriptor.domainName, e); } try { connector.start(); } catch (IOException e) { try { LocateRegistry.createRegistry(descriptor.rmiPort); } catch (RemoteException e2) { throw new ManagementRuntimeException("Cannot start RMI connector for " + descriptor.domainName, e); } try { connector.start(); } catch (IOException e2) { throw new ManagementRuntimeException("Cannot start RMI connector for " + descriptor.domainName, e2); } } assert connector.isActive(); log.info("Started a mbean server : " + url); return server; } @SuppressWarnings("cast") protected MBeanServer doFindServer(String domainName) { for (MBeanServer server : MBeanServerFactory.findMBeanServer(null)) { String domain = server.getDefaultDomain(); if (domain == null || !domain.equals(domainName)) { continue; } return server; } return defaultServer; } protected void doUnregisterLocator(ServerLocatorDescriptor descriptor) { servers.remove(descriptor.domainName); if (descriptor.isDefault) { defaultServer = ManagementFactory.getPlatformMBeanServer(); } } @Override @SuppressWarnings("cast") public MBeanServer lookupServer(ObjectName qualifiedName) { if (defaultServer.isRegistered(qualifiedName)) { return defaultServer; } for (MBeanServer server : MBeanServerFactory.findMBeanServer(null)) { if (server.isRegistered(qualifiedName)) { return server; } } throw new ManagementRuntimeException(qualifiedName + " is not registered"); } @Override public MBeanServer lookupServer() { return defaultServer; } @Override public MBeanServer lookupServer(String domainName) { return doFindServer(domainName); } public void registerLocator(String domain, boolean isDefault) { doRegisterLocator(new ServerLocatorDescriptor(domain, isDefault)); } }