/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF 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.apache.jackrabbit.oak.osgi;
import static com.google.common.base.Preconditions.checkArgument;
import static com.google.common.base.Preconditions.checkNotNull;
import static java.util.Arrays.asList;
import java.util.Collections;
import java.util.Dictionary;
import java.util.Hashtable;
import java.util.List;
import java.util.Map;
import javax.annotation.Nonnull;
import org.apache.jackrabbit.oak.spi.whiteboard.Registration;
import org.apache.jackrabbit.oak.spi.whiteboard.Tracker;
import org.apache.jackrabbit.oak.spi.whiteboard.Whiteboard;
import org.osgi.framework.BundleContext;
import org.osgi.framework.ServiceRegistration;
import org.osgi.util.tracker.ServiceTracker;
/**
* OSGi-based whiteboard implementation.
*/
public class OsgiWhiteboard implements Whiteboard {
private final BundleContext context;
public OsgiWhiteboard(@Nonnull BundleContext context) {
this.context = checkNotNull(context);
}
@Override
public <T> Registration register(
Class<T> type, T service, Map<?, ?> properties) {
checkNotNull(type);
checkNotNull(service);
checkNotNull(properties);
checkArgument(type.isInstance(service));
Dictionary<Object, Object> dictionary = new Hashtable<Object, Object>();
for (Map.Entry<?, ?> entry : properties.entrySet()) {
dictionary.put(entry.getKey(), entry.getValue());
}
final ServiceRegistration registration =
context.registerService(type.getName(), service, dictionary);
return new Registration() {
@Override
public void unregister() {
registration.unregister();
}
};
}
@Override
public <T> Tracker<T> track(Class<T> type) {
checkNotNull(type);
final ServiceTracker tracker =
new ServiceTracker(context, type.getName(), null);
tracker.open();
return new Tracker<T>() {
@Override @SuppressWarnings("unchecked")
public List<T> getServices() {
Object[] services = tracker.getServices();
return (List<T>) (services != null ? asList(services) : Collections.emptyList());
}
@Override
public void stop() {
tracker.close();
}
};
}
}