Mercurial > hg > release > thermostat-0.5
view common/core/src/main/java/com/redhat/thermostat/common/utils/ServiceRegistry.java @ 929:ccac9bcabaa0
Update copyright year of source code
review-thread: http://icedtea.classpath.org/pipermail/thermostat/2013-January/005295.html
reviewed-by: vanaltj
author | Mario Torre <neugens.limasoftware@gmail.com> |
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date | Wed, 23 Jan 2013 16:49:27 +0100 |
parents | 5917cd87fdb4 |
children |
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/* * Copyright 2012, 2013 Red Hat, Inc. * * This file is part of Thermostat. * * Thermostat is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published * by the Free Software Foundation; either version 2, or (at your * option) any later version. * * Thermostat is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License * along with Thermostat; see the file COPYING. If not see * <http://www.gnu.org/licenses/>. * * Linking this code with other modules is making a combined work * based on this code. Thus, the terms and conditions of the GNU * General Public License cover the whole combination. * * As a special exception, the copyright holders of this code give * you permission to link this code with independent modules to * produce an executable, regardless of the license terms of these * independent modules, and to copy and distribute the resulting * executable under terms of your choice, provided that you also * meet, for each linked independent module, the terms and conditions * of the license of that module. An independent module is a module * which is not derived from or based on this code. If you modify * this code, you may extend this exception to your version of the * library, but you are not obligated to do so. If you do not wish * to do so, delete this exception statement from your version. */ package com.redhat.thermostat.common.utils; import java.util.ArrayList; import java.util.Collection; import java.util.Dictionary; import java.util.Enumeration; import java.util.Hashtable; import java.util.Iterator; import java.util.List; import java.util.logging.Logger; import org.osgi.framework.BundleContext; import org.osgi.framework.InvalidSyntaxException; import org.osgi.framework.ServiceReference; import org.osgi.framework.ServiceRegistration; /** * * * @param <T> The type of service which this registry works with. */ public class ServiceRegistry<T> { // Commonly used property keys. public static final String SERVICE_NAME = "servicename"; private final BundleContext context; private final String registrationClass; @SuppressWarnings("rawtypes") private final List<ServiceRegistration> ourRegistrations; private static final Logger log = LoggingUtils.getLogger(ServiceRegistry.class); public ServiceRegistry(BundleContext ctx, String registrationClassName) { context = ctx; registrationClass = registrationClassName; ourRegistrations = new ArrayList<>(); } /** * Register the implementation of T to the OSGi context, with the given properties. * @param service The implementation to be registered. * @param props The additional properties which the service should have. */ public void registerService(T service, Dictionary<String, ?> props) { ServiceRegistration registration = context.registerService(registrationClass, service, props); ourRegistrations.add(registration); } /** * Equivalent to calling registerService(service, props) with a dictionary containing * an entry for SERVICE_NAME with value as name, in adddition to the contents of props * * @param service The implementation to be registered. * @param name The name to be added as SERVICE_NAME property. * @param props Additional properties which the service should be registered with. */ public void registerService(T service, String name, Dictionary<String, String> props) { if (props == null) { props = new Hashtable<String, String>(); } props.put(SERVICE_NAME, name); registerService(service, props); } /** * Equivalent to calling registerService(service, name, props) with null or empty props. * * @param service The implementation to be registered. * @param name The name to be added as SERVICE_NAME property. */ public void registerService(T service, String name) { Hashtable<String, String> props = new Hashtable<>(); props.put(SERVICE_NAME, name); registerService(service, props); } /** * Unregister all of the services that have been registered through this registry. */ @SuppressWarnings("rawtypes") public void unregisterAll() { Iterator<ServiceRegistration> iter = ourRegistrations.iterator(); while (iter.hasNext()) { ServiceRegistration registration = iter.next(); registration.unregister(); iter.remove(); } } /** * Get a implementation of T matching the properties. * * @param props The properties which the returned T implementation must match. * @return A matching T implementation, if any. Otherwise, null. */ public T getService(Dictionary<String, String> props) { ServiceReference[] refs = getServiceRefs(filterFromProps(props)); if (refs == null || refs.length == 0) { return null; } else if (refs.length > 1) { log.info("More than one matching service implementation found."); } ServiceReference ref = refs[0]; return (T) context.getService(ref); } /** * Equivalent to calling getService(props) with a dictionary containing an entry for * SERVICE_NAME with value as name. * * @param name The name for the service which should be returned. * @return An implementation of T matching the supplied name, if any. Otherwise, null. */ public T getService(String name) { Hashtable<String, String> props = new Hashtable<>(); props.put(SERVICE_NAME, name); return getService(props); } private String filterFromProps(Dictionary<String, String> props) { StringBuilder builder = new StringBuilder(); builder.append("(&(objectclass=*)"); if (props != null) { for (Enumeration<String> e = props.keys(); e.hasMoreElements();) { String key = e.nextElement(); String value = props.get(key); builder.append("("); builder.append(key); builder.append("="); builder.append(value); builder.append(")"); } } builder.append(")"); return builder.toString(); } /** * Get all implementations of T which have been registered. This may include ones not * registered through this registry instance. * * @return A collection of all registered T implementations. */ public Collection<T> getRegisteredServices() { ServiceReference[] refs = getServiceRefs(null); List<T> services = new ArrayList<>(); for (ServiceReference ref : refs) { T service = (T) context.getService(ref); services.add(service); } return services; } @SuppressWarnings("unchecked") private ServiceReference[] getServiceRefs(String filter) { ServiceReference[] refs; try { refs = context.getServiceReferences(registrationClass, filter); } catch (InvalidSyntaxException e) { throw (InternalError) new InternalError().initCause(e); } return refs; } }