DatanucleusBridge.java

/*
 * Copyright (c) OSGi Alliance (2013). 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.
 * 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.
 */

package osgi.jpa.managed.datanucleus.adapter;

import java.net.URL;
import java.util.ServiceLoader;
import javax.persistence.spi.PersistenceProvider;
import javax.transaction.TransactionManager;
import org.osgi.framework.Bundle;
import org.osgi.framework.BundleContext;
import org.osgi.framework.BundleEvent;
import org.osgi.framework.ServiceRegistration;
import org.osgi.framework.Version;
import org.osgi.framework.wiring.BundleWiring;
import org.osgi.util.tracker.BundleTracker;
import org.osgi.util.tracker.BundleTrackerCustomizer;
import aQute.bnd.annotation.component.Activate;
import aQute.bnd.annotation.component.Component;
import aQute.bnd.annotation.component.Deactivate;
import aQute.bnd.annotation.component.Reference;

/**
 * Create the persistence provider for Eclipselink and delegate all the messages
 * to it. SPEC:
 */
@Component(provide = {})
@SuppressWarnings("rawtypes")
public class DatanucleusBridge {
	static Version			baseVersion	= new Version("3.2");
	private BundleTracker	bt;

	@Activate
	public void activate(final BundleContext context) {
		bt = new BundleTracker<ServiceRegistration<PersistenceProvider>>(context, Bundle.ACTIVE + Bundle.STARTING,
				new BundleTrackerCustomizer<ServiceRegistration<PersistenceProvider>>() {

					@Override
					public ServiceRegistration<PersistenceProvider> addingBundle(Bundle bundle, BundleEvent event) {
						String name = bundle.getSymbolicName();
						if (name == null || !name.equals("org.datanucleus.api.jpa"))
							return null;

						Version version = bundle.getVersion();
						if (version == null || baseVersion.compareTo(version) > 0)
							return null;

						URL url = bundle.getResource("META-INF/services/" + PersistenceProvider.class.getName());
						if (url == null)
							return null;

						ServiceLoader<PersistenceProvider> sl = ServiceLoader.load(PersistenceProvider.class, bundle
								.adapt(BundleWiring.class).getClassLoader());
						for (PersistenceProvider pp : sl) {
							return bundle.getBundleContext().registerService(PersistenceProvider.class,
									new DatanucleusWrapper(pp), null);
						}
						return null;
					}

					@Override
					public void modifiedBundle(Bundle bundle, BundleEvent event,
							ServiceRegistration<PersistenceProvider> object) {
						// TODO Auto-generated method stub

					}

					@Override
					public void removedBundle(Bundle bundle, BundleEvent event,
							ServiceRegistration<PersistenceProvider> reg) {
						reg.unregister();
					}
				});
		bt.open();
	}

	@Deactivate
	void deactivate() {
		this.bt.close();
	}

	@Reference
	void setTm(TransactionManager tm) {
		// EclipselinkTransactionController.tm = tm;
	}

}