| /******************************************************************************* |
| * Copyright (c) 2008, 2013 IBM Corporation and others. |
| * |
| * This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License 2.0 |
| * which accompanies this distribution, and is available at |
| * https://www.eclipse.org/legal/epl-2.0/ |
| * |
| * SPDX-License-Identifier: EPL-2.0 |
| * |
| * Contributors: |
| * IBM Corporation - initial API and implementation |
| *******************************************************************************/ |
| |
| package org.eclipse.equinox.internal.transforms; |
| |
| import java.util.HashMap; |
| import org.eclipse.osgi.framework.log.FrameworkLogEntry; |
| import org.eclipse.osgi.internal.framework.EquinoxContainer; |
| import org.eclipse.osgi.internal.log.EquinoxLogServices; |
| import org.osgi.framework.*; |
| import org.osgi.util.tracker.ServiceTracker; |
| |
| /** |
| * A dynamic list of transformers. |
| */ |
| public class TransformerList extends ServiceTracker<Object, Object> { |
| |
| /** |
| * The stale state of this list. Set to true every time a new matching service instance is detected. |
| */ |
| private volatile boolean stale = true; |
| |
| /** |
| * Local cache of transformers. |
| */ |
| private HashMap<String, StreamTransformer> transformers = new HashMap<String, StreamTransformer>(); |
| private final EquinoxLogServices logServices; |
| |
| /** |
| * Create a new instance of this list. |
| * @param context the context to track |
| * @throws InvalidSyntaxException thrown if there's an issue listening for changes to the given transformer type |
| */ |
| public TransformerList(BundleContext context, EquinoxLogServices logServices) throws InvalidSyntaxException { |
| super(context, context.createFilter("(&(objectClass=" //$NON-NLS-1$ |
| + Object.class.getName() + ")(" + TransformTuple.TRANSFORMER_TYPE //$NON-NLS-1$ |
| + "=*))"), null); //$NON-NLS-1$ |
| this.logServices = logServices; |
| open(); |
| } |
| |
| /** |
| * Return the transformer of the given type being monitored by this list. |
| * If the list is stale it will first be rebuilt. |
| * @param type the type of transformer |
| * @return the transformer or null if no transformer of the given type is available. |
| */ |
| public synchronized StreamTransformer getTransformer(String type) { |
| if (stale) { |
| rebuildTransformersMap(); |
| } |
| return transformers.get(type); |
| } |
| |
| public synchronized boolean hasTransformers() { |
| if (stale) { |
| rebuildTransformersMap(); |
| } |
| return transformers.size() > 0; |
| } |
| |
| /** |
| * Consults the bundle context for services of the transformer type and builds the internal cache. |
| */ |
| private void rebuildTransformersMap() { |
| transformers.clear(); |
| ServiceReference<Object>[] serviceReferences = getServiceReferences(); |
| stale = false; |
| if (serviceReferences == null) |
| return; |
| |
| for (ServiceReference<Object> serviceReference : serviceReferences) { |
| String type = serviceReference.getProperty(TransformTuple.TRANSFORMER_TYPE).toString(); |
| if (type == null || transformers.get(type) != null) |
| continue; |
| Object object = getService(serviceReference); |
| if (object instanceof StreamTransformer) |
| transformers.put(type, (StreamTransformer) object); |
| else { |
| ProxyStreamTransformer transformer; |
| try { |
| transformer = new ProxyStreamTransformer(object); |
| transformers.put(type, transformer); |
| } catch (SecurityException | NoSuchMethodException e) { |
| logServices.log(EquinoxContainer.NAME, FrameworkLogEntry.ERROR, "Problem creating transformer", e); //$NON-NLS-1$ |
| } |
| } |
| } |
| } |
| |
| public Object addingService(ServiceReference<Object> reference) { |
| try { |
| return super.addingService(reference); |
| } finally { |
| stale = true; |
| } |
| } |
| |
| public void modifiedService(ServiceReference<Object> reference, Object service) { |
| super.modifiedService(reference, service); |
| stale = true; |
| } |
| |
| public void removedService(ServiceReference<Object> reference, Object service) { |
| super.removedService(reference, service); |
| stale = true; |
| } |
| } |