core/src/main/java/org/jclouds/osgi/Activator.java

/**
 * Licensed to jclouds, Inc. (jclouds) under one or more
 * contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  jclouds licenses this file
 * to you 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 org.jclouds.osgi;

import org.jclouds.providers.ProviderRegistry;
import org.osgi.framework.BundleActivator;
import org.osgi.framework.BundleContext;

public class Activator implements BundleActivator {

  ProviderBundleListener bundleListener = new ProviderBundleListener();

  /**
   * Called when this bundle is started so the Framework can perform the
   * bundle-specific activities necessary to start this bundle. This method
   * can be used to register services or to allocate any resources that this
   * bundle needs.
   * <p/>
   * <p/>
   * This method must complete and return to its caller in a timely manner.
   *
   * @param context The execution context of the bundle being started.
   * @throws Exception If this method throws an exception, this
   *                   bundle is marked as stopped and the Framework will remove this
   *                   bundle's listeners, unregister all services registered by this
   *                   bundle, and release all services used by this bundle.
   */
  @Override
  public void start(BundleContext context) throws Exception {
    context.addBundleListener(bundleListener);
  }

  /**
   * Called when this bundle is stopped so the Framework can perform the
   * bundle-specific activities necessary to stop the bundle. In general, this
   * method should undo the work that the <code>BundleActivator.start</code>
   * method started. There should be no active threads that were started by
   * this bundle when this bundle returns. A stopped bundle must not call any
   * Framework objects.
   * <p/>
   * <p/>
   * This method must complete and return to its caller in a timely manner.
   *
   * @param context The execution context of the bundle being stopped.
   * @throws Exception If this method throws an exception, the
   *                   bundle is still marked as stopped, and the Framework will remove
   *                   the bundle's listeners, unregister all services registered by the
   *                   bundle, and release all services used by the bundle.
   */
  @Override
  public void stop(BundleContext context) throws Exception {
    context.removeBundleListener(bundleListener);
    ProviderRegistry.clear();
  }
}