/*
* 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.jclouds.karaf.cache.utils;
import org.jclouds.karaf.cache.CacheManager;
import org.jclouds.karaf.cache.Cacheable;
import org.osgi.framework.BundleContext;
import org.osgi.framework.FrameworkUtil;
import org.osgi.framework.InvalidSyntaxException;
import org.osgi.framework.ServiceReference;
import org.osgi.util.tracker.ServiceTracker;
import com.google.common.reflect.TypeToken;
public class CacheUtils {
private CacheUtils() {
//Utility Class
}
/**
* Creates a {@link ServiceTracker} that upon Service Registration, it binds the Service to the {@link CacheManager}.
* @param context
* @param serviceClass
* @param cacheManager
* @param <T>
* @return
*/
public static <T> ServiceTracker createServiceCacheTracker(final BundleContext context, final Class<T> serviceClass, final CacheManager<T> cacheManager) {
return new ServiceTracker(context, serviceClass.getName(), null) {
@Override
public Object addingService(ServiceReference reference) {
Object service = super.addingService(reference);
if (serviceClass.isAssignableFrom(service.getClass())) {
cacheManager.bindService((T) service);
}
return service;
}
@Override
public void removedService(ServiceReference reference, Object service) {
if (serviceClass.isAssignableFrom(service.getClass())) {
cacheManager.unbindService((T) service);
}
super.removedService(reference, service);
}
};
}
public static <T> ServiceTracker createServiceCacheTracker(final BundleContext context, final TypeToken<T> serviceToken, final CacheManager<T> cacheManager) {
return new ServiceTracker(context, serviceToken.getRawType().getName(), null) {
@Override
public Object addingService(ServiceReference reference) {
Object service = super.addingService(reference);
if (serviceToken.isAssignableFrom(service.getClass())) {
cacheManager.bindService((T) service);
}
return service;
}
@Override
public void removedService(ServiceReference reference, Object service) {
if (serviceToken.isAssignableFrom(service.getClass())) {
cacheManager.unbindService((T) service);
}
super.removedService(reference, service);
}
};
}
/**
* Creates a {@link ServiceTracker} which binds {@link org.jclouds.karaf.cache.Cacheable} to {@link CacheManager}.
* @param context
* @param cacheManager
* @return
*/
public static <T> ServiceTracker createCacheableTracker(final BundleContext context, final String type, final CacheManager<T> cacheManager) throws InvalidSyntaxException {
return new ServiceTracker(context, FrameworkUtil.createFilter("(&(cache-type="+type+")(objectClass=org.jclouds.karaf.cache.Cacheable))"), null) {
@Override
public Object addingService(ServiceReference reference) {
Object service = super.addingService(reference);
if (Cacheable.class.isAssignableFrom(service.getClass())) {
cacheManager.bindCacheable((Cacheable) service);
}
return service;
}
@Override
public void removedService(ServiceReference reference, Object service) {
if (Cacheable.class.isAssignableFrom(service.getClass())) {
cacheManager.unbindCacheable((Cacheable) service);
}
super.removedService(reference, service);
}
};
}
}