Java tutorial
/* * Copyright (c) 2006-2011 Nuxeo SA (http://nuxeo.com/) and others. * * All rights reserved. This program and the accompanying materials * are made available under the terms of the Eclipse Public License v1.0 * which accompanies this distribution, and is available at * http://www.eclipse.org/legal/epl-v10.html * * Contributors: * Nuxeo - initial API and implementation * * $Id$ */ package org.eclipse.ecr.runtime.api; import java.net.URI; import java.util.HashMap; import java.util.List; import java.util.Map; import java.util.Vector; import javax.naming.NameNotFoundException; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; /** * @author <a href="mailto:bs@nuxeo.com">Bogdan Stefanescu</a> * */ public final class ServiceManager implements org.eclipse.ecr.runtime.ServiceManager { private static final Log log = LogFactory.getLog(ServiceManager.class); private static final ServiceManager instance = new ServiceManager(); private final Map<String, ServiceDescriptor> services = new HashMap<String, ServiceDescriptor>(); private final List<ServiceHost> servers = new Vector<ServiceHost>(); private final Map<String, ServiceGroup> groups = new HashMap<String, ServiceGroup>(); // Singleton. private ServiceManager() { } public static ServiceManager getInstance() { return instance; } public ServiceDescriptor[] getServiceDescriptors() { return services.values().toArray(new ServiceDescriptor[services.size()]); } public ServiceDescriptor getServiceDescriptor(Class<?> serviceClass) { return getServiceDescriptor(serviceClass.getName()); } public ServiceDescriptor getServiceDescriptor(String serviceClass) { return services.get(serviceClass); } public ServiceDescriptor getServiceDescriptor(Class<?> serviceClass, String name) { return getServiceDescriptor(serviceClass.getName(), name); } public ServiceDescriptor getServiceDescriptor(String serviceClass, String name) { return services.get(serviceClass + '#' + name); } public void registerService(ServiceDescriptor sd) { String key = sd.getInstanceName(); synchronized (services) { if (services.containsKey(key)) { String msg = "Duplicate service registration: " + key; log.error(msg); Framework.getRuntime().getWarnings().add(msg); return; } services.put(key, sd); sd.getGroup().addService(sd); log.info("Registered service: " + key); } } public void unregisterService(ServiceDescriptor sd) { String key = sd.getInstanceName(); synchronized (services) { sd = services.remove(key); if (sd == null) { log.warn(String.format( "Cannot unregister service '%s': either already" + " unregistered or not registered at all", key)); } else { sd.getGroup().removeService(sd); log.info("Unregistered service: " + key); } } } @Override @SuppressWarnings("unchecked") public <T> T getService(Class<T> serviceClass) throws Exception { ServiceDescriptor sd = services.get(serviceClass.getName()); if (sd != null) { try { T svc = (T) sd.getGroup().getServer().lookup(sd); if (svc != null) { return svc; } } catch (NameNotFoundException e) { // When all facades are deployed (JBoss for now), then lookup // errors are legitimate. Otherwise it may be just a bad // packaging issue, so don't log. TODO fix packaging if (J2EEContainerDescriptor.getSelected() == J2EEContainerDescriptor.JBOSS) { log.warn("Existing binding but unreachable service for " + serviceClass.getName() + " ! Fallback on local service..."); log.debug(e.getMessage() + " Check binding declaration: " + sd.toString()); } } } return Framework.getLocalService(serviceClass); } @Override @SuppressWarnings("unchecked") public <T> T getService(Class<T> serviceClass, String name) throws Exception { ServiceDescriptor sd = services.get(serviceClass.getName() + '#' + name); log.trace("Known services" + services.keySet().toString()); if (sd == null) { return Framework.getLocalService(serviceClass); } return (T) sd.getGroup().getServer().lookup(sd); } /** * Dynamically lookup services given a service URI. * <p> * This is a dynamic lookup in the sense that the service bindings should * not be registered through extension points but all the information about * how to locate the service are passed through the URI. * <p> * This method is not portable since the URI depends on the target server * and configuration. Examples of service URIs: * <ul> * <li><code>jboss://localhost:1099/nuxeo/TypeManagerBean/remote</code> - * locate a service on jboss</li> * <li><code>glassfish://localhost:1234/org.nuxeo.ecm.platform.types.TypeManager</code> - * locate a service on glassfish</li> * </ul> * * @param serviceUri the service uri * @return the service */ public Object getService(String serviceUri) throws Exception { URI uri = new URI(serviceUri); ServiceLocatorFactory factory = ServiceLocatorFactory.getFactory(uri.getScheme()); if (factory != null) { ServiceLocator locator = factory.createLocator(uri); return locator.lookup(uri.getPath().substring(1)); // avoid leading / } return null; } public ServiceGroup getOrCreateGroup(String name) { if (name == null || name.length() == 0) { name = "*"; } synchronized (groups) { ServiceGroup group = groups.get(name); if (group == null) { group = new ServiceGroup(name); groups.put(name, group); } return group; } } public ServiceGroup getGroup(String name) { synchronized (groups) { return groups.get(name); } } public void removeGroup(String name) { synchronized (groups) { groups.remove(name); } } public void addGroup(String name) { if (name == null || name.length() == 0) { name = "*"; } ServiceGroup group = new ServiceGroup(name); synchronized (groups) { groups.put(name, group); } } public ServiceGroup getRootGroup() { return getOrCreateGroup("*"); } public void registerServer(ServiceHost server) { servers.add(server); } public void unregisterServer(ServiceHost server) { servers.remove(server); server.dispose(); } /** * Removes all registered servers. */ public void removeServers() { for (ServiceHost server : servers) { server.dispose(); } servers.clear(); } public void removeServices() { services.clear(); } public void removeGroups() { groups.clear(); } public void reset() { removeServices(); removeGroups(); removeServers(); } public ServiceHost[] getServers() { return servers.toArray(new ServiceHost[servers.size()]); } }