AbstractSessionHolderProviderManager.java

/**
 * Copyright 2009 the original author or authors
 *
 *    Licensed 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.springframework.extensions.jcr.support;

import java.util.List;

import javax.jcr.Repository;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.extensions.jcr.SessionHolderProvider;
import org.springframework.extensions.jcr.SessionHolderProviderManager;

/**
 * Base implementation for SessionHolderProviderManager that adds most of the functionality needed by the
 * interface. Usually interface implementations will extends this class.
 * @author Costin Leau
 * @author Sergio Bossa
 * @author Salvatore Incandela
 */
public abstract class AbstractSessionHolderProviderManager implements SessionHolderProviderManager {

    protected static final Logger LOG = LoggerFactory.getLogger(AbstractSessionHolderProviderManager.class);

    protected SessionHolderProvider defaultProvider = new GenericSessionHolderProvider();

    /**
     * Returns all the providers for this class. Subclasses have to implement this method.
     * @return sessionHolderProviders
     */
    public abstract List<SessionHolderProvider> getProviders();

    /**
     * @see org.springframework.extensions.jcr.SessionHolderProviderManager#getSessionProvider(Repository)
     */
    public SessionHolderProvider getSessionProvider(Repository repository) {
        // graceful fallback
        if (repository == null)
            return defaultProvider;

        String key = repository.getDescriptor(Repository.REP_NAME_DESC);
        List<SessionHolderProvider> providers = getProviders();

        // search the provider
        for (int i = 0; i < providers.size(); i++) {
            SessionHolderProvider provider = providers.get(i);
            if (provider.acceptsRepository(key)) {
                if (LOG.isDebugEnabled())
                    LOG.debug("specific SessionHolderProvider found for repository " + key);
                return provider;
            }
        }

        // no provider found - return the default one
        if (LOG.isDebugEnabled())
            LOG.debug("no specific SessionHolderProvider found for repository " + key + "; using the default one");
        return defaultProvider;
    }
}