Java tutorial
/* * (C) Copyright 2006-2011 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: * Nuxeo - initial API and implementation * * $Id$ */ package org.nuxeo.runtime.osgi; import java.net.URL; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.nuxeo.common.Environment; import org.nuxeo.runtime.api.Framework; import org.osgi.framework.Bundle; import org.osgi.framework.BundleActivator; import org.osgi.framework.BundleContext; import org.osgi.framework.ServiceReference; import org.osgi.service.packageadmin.PackageAdmin; /** * The default BundleActivator for NXRuntime over an OSGi comp. platform. * * @author <a href="mailto:bs@nuxeo.com">Bogdan Stefanescu</a> */ public class OSGiRuntimeActivator implements BundleActivator { private static final Log log = LogFactory.getLog(OSGiRuntimeActivator.class); private static OSGiRuntimeActivator instance; protected OSGiRuntimeService runtime; protected OSGiComponentLoader componentLoader; protected ServiceReference pkgAdmin; protected BundleContext context; public static OSGiRuntimeActivator getInstance() { return instance; } @Override public void start(BundleContext context) { log.info("Starting Runtime Activator"); instance = this; this.context = context; pkgAdmin = context.getServiceReference(PackageAdmin.class.getName()); // assert the environment is setup if (Environment.getDefault() == null) { throw new IllegalStateException("Environment is not setup"); } // create the runtime runtime = new OSGiRuntimeService(context); // load main config file if any URL config = context.getBundle().getResource("/OSGI-INF/nuxeo.properties"); if (config != null) { System.setProperty(OSGiRuntimeService.PROP_CONFIG_DIR, config.toExternalForm()); } initialize(runtime); // start it Framework.initialize(runtime); // register bundle component loader componentLoader = new OSGiComponentLoader(runtime); // TODO register osgi services } @Override public void stop(BundleContext context) { log.info("Stopping Runtime Activator"); instance = null; pkgAdmin = null; // remove component loader componentLoader.uninstall(); componentLoader = null; // unregister Framework.shutdown(); uninitialize(runtime); runtime = null; context = null; } public Bundle getBundle(String name) { if (pkgAdmin == null) { return null; } PackageAdmin pa = (PackageAdmin) context.getService(pkgAdmin); Bundle[] bundles = pa.getBundles(name, null); context.ungetService(pkgAdmin); return bundles == null ? null : bundles[0]; } /** * Load a class from another bundle given its reference as <code>bundleSymbolicName:className</code> If no * <code>bundleSymbolicName:</code> prefix is given then a classForName will be done * * @param ref * @return */ public Class<?> loadClass(String ref) throws ReflectiveOperationException { int i = ref.indexOf(':'); if (i == -1) { return Class.forName(ref); } return loadClass(ref.substring(0, i), ref.substring(i + 1)); } public Class<?> loadClass(String bundleName, String className) throws ReflectiveOperationException { Bundle bundle = getBundle(bundleName); if (bundle == null) { throw new ClassNotFoundException( "No bundle found with name: " + bundleName + ". Unable to load class " + className); } return bundle.loadClass(className); } public Object newInstance(String ref) throws ReflectiveOperationException { return loadClass(ref).newInstance(); } public Object newInstance(String bundleName, String className) throws ReflectiveOperationException { return loadClass(bundleName, className).newInstance(); } /** * Gives a chance to derived classes to initialize them before the runtime is started. * * @param runtime the current runtime */ protected void initialize(OSGiRuntimeService runtime) { // do nothing } /** * Gives a chance to derived classes to uninitialize them after the runtime is stopped. * * @param runtime the current runtime */ protected void uninitialize(OSGiRuntimeService runtime) { // do nothing } }