jax-rs.whiteboard/src/main/java/org/apache/aries/jax/rs/whiteboard/internal/FiltersAndInterceptorsServiceTrackerCustomizer.java

/*
 * 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.aries.jax.rs.whiteboard.internal;

import org.osgi.framework.BundleContext;
import org.osgi.framework.ServiceReference;
import org.osgi.util.tracker.ServiceTracker;
import org.osgi.util.tracker.ServiceTrackerCustomizer;

public class FiltersAndInterceptorsServiceTrackerCustomizer
    implements ServiceTrackerCustomizer<Object, ServiceTracker<?, ?>> {

    private BundleContext _bundleContext;

    public FiltersAndInterceptorsServiceTrackerCustomizer(
        BundleContext bundleContext) {

        _bundleContext = bundleContext;
    }

    @Override
    public ServiceTracker<?, ?> addingService(final ServiceReference<Object> reference) {
        final String filterBase =
            reference.getProperty("osgi.jaxrs.filter.base").toString();

        final Object service = _bundleContext.getService(reference);

        ServiceTracker<CXFJaxRsServiceRegistrator, CXFJaxRsServiceRegistrator> serviceTracker = new ServiceTracker<>(
            _bundleContext, CXFJaxRsServiceRegistrator.class,
            new ServiceTrackerCustomizer
                <CXFJaxRsServiceRegistrator, CXFJaxRsServiceRegistrator>() {

                @Override
                public CXFJaxRsServiceRegistrator addingService(
                    ServiceReference<CXFJaxRsServiceRegistrator> cxfReference) {

                    Object resourceBaseObject =
                        cxfReference.getProperty("CXF_ENDPOINT_ADDRESS");

                    if (resourceBaseObject == null) {
                        return null;
                    }

                    String resourceBase = resourceBaseObject.toString();

                    if (resourceBase.startsWith(filterBase)) {
                        CXFJaxRsServiceRegistrator serviceRegistrator =
                            _bundleContext.getService(cxfReference);
                        try {
                            serviceRegistrator.add(service);

                            return serviceRegistrator;
                        }
                        finally {
                            _bundleContext.ungetService(reference);
                        }
                    }

                    return null;
                }

                @Override
                public void modifiedService(
                    ServiceReference<CXFJaxRsServiceRegistrator> reference,
                    CXFJaxRsServiceRegistrator serviceRegistrator) {

                    removedService(reference, serviceRegistrator);
                    addingService(reference);
                }

                @Override
                public void removedService(
                    ServiceReference<CXFJaxRsServiceRegistrator> reference,
                    CXFJaxRsServiceRegistrator serviceRegistrator) {

                    try {
                        serviceRegistrator.remove(service);
                    }
                    finally {
                        _bundleContext.ungetService(reference);
                    }
                }
            });

        serviceTracker.open();

        return serviceTracker;
    }

    @Override
    public void modifiedService(
        ServiceReference<Object> reference, ServiceTracker<?, ?> serviceTracker) {

        removedService(reference, serviceTracker);
        addingService(reference);
    }

    @Override
    public void removedService(
        ServiceReference<Object> reference, ServiceTracker<?, ?> serviceTracker) {

        _bundleContext.ungetService(reference);

        serviceTracker.close();
    }
}