Bug 254021 Implement new LinkBundleFactory service (rfc 138)

1 files changed, 178 insertions, 0 deletions

diff --git a/bundles/org.eclipse.osgi/core/composite/org/eclipse/osgi/internal/composite/CompositeServiceTracker.java b/bundles/org.eclipse.osgi/core/composite/org/eclipse/osgi/internal/composite/CompositeServiceTracker.java
new file mode 100644
index 000000000..a9a449b40
--- /dev/null
+++ b/bundles/org.eclipse.osgi/core/composite/org/eclipse/osgi/internal/composite/CompositeServiceTracker.java
@@ -0,0 +1,178 @@
+/*******************************************************************************
+ * Copyright (c) 2008 IBM Corporation and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ * 
+ * Contributors:
+ *     IBM Corporation - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.osgi.internal.composite;
+
+import java.util.*;
+import org.eclipse.osgi.util.ManifestElement;
+import org.osgi.framework.*;
+import org.osgi.util.tracker.ServiceTracker;
+import org.osgi.util.tracker.ServiceTrackerCustomizer;
+
+class CompositeServiceTracker implements ServiceTrackerCustomizer {
+	final BundleContext sourceContext;
+	final BundleContext targetContext;
+	final ServiceTracker[] trackers;
+	final String[] filters;
+	/* @GuardedBy("serviceComposites") */
+	final HashMap serviceComposites = new HashMap();
+
+	public CompositeServiceTracker(BundleContext sourceContext, BundleContext targetContext, String serviceFilters) {
+		this.sourceContext = sourceContext;
+		this.targetContext = targetContext;
+		filters = ManifestElement.getArrayFromList(serviceFilters, ","); //$NON-NLS-1$
+		trackers = new ServiceTracker[filters.length];
+	}
+
+	synchronized void open() {
+		for (int i = 0; i < trackers.length; i++) {
+			try {
+				trackers[i] = new ServiceTracker(sourceContext, sourceContext.createFilter(filters[i]), this);
+				trackers[i].open();
+			} catch (InvalidSyntaxException e) {
+				// TODO log
+				// we will skip this filter; note that trackers may have null entries
+			}
+		}
+	}
+
+	synchronized void close() {
+		for (int i = 0; i < trackers.length; i++) {
+			if (trackers[i] != null)
+				trackers[i].close();
+		}
+	}
+
+	public Object addingService(ServiceReference reference) {
+		ServiceLink serviceLink;
+		int useCount;
+		synchronized (serviceComposites) {
+			serviceLink = (ServiceLink) serviceComposites.get(reference);
+			if (serviceLink == null) {
+				serviceLink = new ServiceLink(reference);
+				serviceComposites.put(reference, serviceLink);
+			}
+			useCount = serviceLink.incrementUse();
+		}
+		// register service outside of the sync block
+		if (useCount == 1)
+			serviceLink.register();
+		return serviceLink;
+	}
+
+	public void modifiedService(ServiceReference reference, Object service) {
+		ServiceLink serviceLink = (ServiceLink) service;
+		Dictionary serviceProps = null;
+		synchronized (serviceComposites) {
+			serviceProps = serviceLink.getRefreshProperties();
+		}
+		// set service properties out side the sync block
+		if (serviceProps != null)
+			((ServiceLink) service).setServiceProperties(serviceProps);
+	}
+
+	public void removedService(ServiceReference reference, Object service) {
+		int useCount;
+		synchronized (serviceComposites) {
+			useCount = ((ServiceLink) service).decrementUse();
+			if (useCount == 0)
+				serviceComposites.remove(reference);
+		}
+		// unregister outside the sync block
+		if (useCount == 0)
+			((ServiceLink) service).unregister();
+	}
+
+	class ServiceLink implements ServiceFactory {
+		private final ServiceReference reference;
+		private volatile ServiceRegistration registration;
+		/* @GuardedBy("this") */
+		private Object service;
+		/* @GuardedBy("serviceLinks") */
+		private int useCount;
+
+		ServiceLink(ServiceReference reference) {
+			this.reference = reference;
+		}
+
+		/* @GuardedBy("serviceLinks") */
+		Dictionary getRefreshProperties() {
+			Dictionary result = getServiceProperties();
+			if (useCount <= 1)
+				return result;
+			// need to do an expensive properties check to avoid multiple registration property changes
+			String[] originalKeys = registration.getReference().getPropertyKeys();
+			for (int i = 0; i < originalKeys.length; i++) {
+				if (!Constants.OBJECTCLASS.equals(originalKeys[i]) && !Constants.SERVICE_ID.equals(originalKeys[i]))
+					// identity compare is done on purpose here to catch any kind of change
+					if (registration.getReference().getProperty(originalKeys[i]) != result.get(originalKeys[i]))
+						return result;
+			}
+			for (Enumeration eKeys = result.keys(); eKeys.hasMoreElements();) {
+				String key = (String) eKeys.nextElement();
+				if (!Constants.OBJECTCLASS.equals(key) && !Constants.SERVICE_ID.equals(key))
+					// identity compare is done on purpose here to catch any kind of change
+					if (result.get(key) != registration.getReference().getProperty(key))
+						return result;
+			}
+			return null;
+		}
+
+		/* @GuardedBy("serviceLinks") */
+		int decrementUse() {
+			return --useCount;
+		}
+
+		/* @GuardedBy("serviceLinks") */
+		int incrementUse() {
+			return ++useCount;
+		}
+
+		/* @GuardedBy("serviceLinks") */
+		int getUse() {
+			return useCount;
+		}
+
+		void setServiceProperties(Dictionary props) {
+			ServiceRegistration current = registration;
+			if (current != null)
+				current.setProperties(props);
+		}
+
+		void register() {
+			Dictionary props = getServiceProperties();
+			registration = targetContext.registerService((String[]) props.get(Constants.OBJECTCLASS), this, props);
+		}
+
+		void unregister() {
+			ServiceRegistration current = registration;
+			if (current != null)
+				current.unregister();
+		}
+
+		private Dictionary getServiceProperties() {
+			String[] keys = reference.getPropertyKeys();
+			Hashtable serviceProps = new Hashtable(keys.length);
+			for (int i = 0; i < keys.length; i++)
+				serviceProps.put(keys[i], reference.getProperty(keys[i]));
+			return serviceProps;
+		}
+
+		public synchronized Object getService(Bundle bundle, ServiceRegistration reg) {
+			if (service == null)
+				service = sourceContext.getService(reference);
+			return service;
+		}
+
+		public void ungetService(Bundle bundle, ServiceRegistration reg, Object serv) {
+			// nothing
+		}
+	}
+}