EntityProviderAutoRegistrar.java

/**
 * $Id: EntityProviderAutoRegistrar.java 105077 2012-02-24 22:54:29Z ottenhoff@longsight.com $
 * $URL: https://source.sakaiproject.org/svn/entitybroker/trunk/utils/src/java/org/sakaiproject/entitybroker/util/spring/EntityProviderAutoRegistrar.java $
 * EBlogic.java - entity-broker - Apr 15, 2008 4:29:18 PM - azeckoski
 **************************************************************************
 * Copyright (c) 2007, 2008, 2009 The Sakai Foundation
 *
 * Licensed under the Educational Community 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.opensource.org/licenses/ECL-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.sakaiproject.entitybroker.util.spring;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.sakaiproject.entitybroker.entityprovider.EntityProvider;
import org.sakaiproject.entitybroker.entityprovider.EntityProviderManager;
import org.sakaiproject.entitybroker.entityprovider.capabilities.AutoRegisterEntityProvider;
import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;

/**
 * Finds and registers any {@link EntityProvider} implementation which also implements
 * {@link AutoRegisterEntityProvider}
 * 
 * @author Antranig Basman (antranig@caret.cam.ac.uk)
 * @author Aaron Zeckoski (aaronz@vt.edu)
 */
public class EntityProviderAutoRegistrar implements ApplicationContextAware {

    private static Log log = LogFactory.getLog(EntityProviderAutoRegistrar.class);

    EntityProviderManager entityProviderManager;
    public void setEntityProviderManager(EntityProviderManager entityProviderManager) {
        this.entityProviderManager = entityProviderManager;
    }

    protected EntityProviderAutoRegistrar() { }

    /**
     * Construct the auto-registrar which will search the spring app context and will register all
     * entity providers found in it which implement {@link AutoRegisterEntityProvider}
     * @param entityProviderManager the entityProviderManager service which is used for registration
     */
    public EntityProviderAutoRegistrar(EntityProviderManager entityProviderManager) {
        super();
        this.entityProviderManager = entityProviderManager;
        init();
    }

    public void init() {
        log.info("init");
    }

    public void setApplicationContext(ApplicationContext context) throws BeansException {
        log.debug("setAC: " + context.getDisplayName());
        String[] autobeans = context.getBeanNamesForType(AutoRegisterEntityProvider.class, false, false);
        StringBuilder registeredPrefixes = new StringBuilder();
        for (String autobean : autobeans) {
            AutoRegisterEntityProvider register = (AutoRegisterEntityProvider) context
            .getBean(autobean);
            if (register.getEntityPrefix() == null || register.getEntityPrefix().equals("")) {
                // should this die here or is this error log enough? -AZ
                log.error("Could not autoregister EntityProvider because the enity prefix is null or empty string for class: "
                        + register.getClass().getName());
            } else {
                registeredPrefixes.append(" : " + register.getEntityPrefix());
                entityProviderManager.registerEntityProvider(register);
            }
        }
        log.info("AutoRegistered EntityProvider prefixes " + registeredPrefixes);
        // TODO - deal with de-registration in the case we ever support dynamic contexts.
    }

}