ConfigPersistenceServiceFactory.java

/**
 * Licensed to the Austrian Association for Software Tool Integration (AASTI)
 * under one or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information regarding copyright
 * ownership. The AASTI 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.openengsb.core.persistence.internal;

import java.util.Dictionary;
import java.util.HashMap;
import java.util.Hashtable;

import org.openengsb.core.api.Constants;
import org.openengsb.core.api.OsgiServiceNotAvailableException;
import org.openengsb.core.api.OsgiUtilsService;
import org.openengsb.core.api.persistence.ConfigPersistenceBackendService;
import org.openengsb.core.api.persistence.ConfigPersistenceService;
import org.openengsb.core.util.DefaultOsgiUtilsService;
import org.openengsb.core.util.FilterUtils;
import org.osgi.framework.BundleContext;
import org.osgi.framework.Filter;
import org.osgi.framework.ServiceRegistration;
import org.osgi.service.cm.ConfigurationException;
import org.osgi.service.cm.ManagedServiceFactory;

/**
 * Service factory managed by Configuration and Fileinstall OSGi services in play.
 */
public class ConfigPersistenceServiceFactory implements ManagedServiceFactory {

    private BundleContext bundleContext;
    private OsgiUtilsService serviceUtils;

    private HashMap<String, ServiceRegistration> serviceMap =
        new HashMap<String, ServiceRegistration>();

    @Override
    public String getName() {
        return "Configuration Persistence Service Factory";
    }

    @Override
    @SuppressWarnings({ "rawtypes" })
    public synchronized void updated(String pid, Dictionary properties) throws ConfigurationException {
        preconditionPropertyExists(Constants.BACKEND_ID, properties);
        preconditionPropertyExists(Constants.CONFIGURATION_ID, properties);
        deleted(pid);
        setupConfigPersistenceService(pid, properties);
    }

    @SuppressWarnings({ "rawtypes", "unchecked" })
    private void setupConfigPersistenceService(String pid, Dictionary properties) throws ConfigurationException {
        ConfigPersistenceBackendService backendService = retrieveBackendService(properties);
        DefaultConfigPersistenceService configPersistenceService = new DefaultConfigPersistenceService(backendService);
        Dictionary exportProperties = new Hashtable();
        exportProperties.put(Constants.CONFIGURATION_ID, properties.get(Constants.CONFIGURATION_ID));
        ServiceRegistration registration =
            bundleContext.registerService(ConfigPersistenceService.class.getName(), configPersistenceService,
                exportProperties);
        serviceMap.put(pid, registration);
    }

    @SuppressWarnings("rawtypes")
    private ConfigPersistenceBackendService retrieveBackendService(Dictionary properties)
        throws ConfigurationException {
        try {
            Filter serviceProxyFilter = FilterUtils.makeFilter(ConfigPersistenceBackendService.class,
                String.format("(%s=%s)", Constants.BACKEND_ID, properties.get(Constants.BACKEND_ID)));
            return serviceUtils.getOsgiServiceProxy(serviceProxyFilter, ConfigPersistenceBackendService.class);
        } catch (OsgiServiceNotAvailableException e) {
            throw new ConfigurationException(Constants.BACKEND_ID, String.format(
                "backend service %s could not be found; please recheck documentation",
                properties.get(Constants.BACKEND_ID)), e);
        }
    }

    @SuppressWarnings("rawtypes")
    private void preconditionPropertyExists(String key, Dictionary properties) throws ConfigurationException {
        if (properties.get(key) == null) {
            throw new ConfigurationException(key,
                String.format("Property %s is required to configure a ConfigPersistenceService correctly", key));
        }
    }

    @Override
    public synchronized void deleted(String pid) {
        if (!serviceMap.containsKey(pid)) {
            return;
        }
        serviceMap.get(pid).unregister();
    }

    public void setBundleContext(BundleContext bundleContext) {
        this.bundleContext = bundleContext;
        DefaultOsgiUtilsService defaultOsgiUtilsService = new DefaultOsgiUtilsService();
        defaultOsgiUtilsService.setBundleContext(bundleContext);
        serviceUtils = defaultOsgiUtilsService;
    }

}