net.solarnetwork.central.dras.aop.EntityChangeNotificationAspect.java Source code

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Here is the source code for net.solarnetwork.central.dras.aop.EntityChangeNotificationAspect.java

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/* ==================================================================
 * EntityChangeNotificationAspect.java - Jun 28, 2011 3:02:14 PM
 * 
 * Copyright 2007-2011 SolarNetwork.net Dev Team
 * 
 * This program is free software; you can redistribute it and/or 
 * modify it under the terms of the GNU General Public License as 
 * published by the Free Software Foundation; either version 2 of 
 * the License, or (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful, 
 * but WITHOUT ANY WARRANTY; without even the implied warranty of 
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 
 * General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License 
 * along with this program; if not, write to the Free Software 
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 
 * 02111-1307 USA
 * ==================================================================
 * $Id$
 * ==================================================================
 */

package net.solarnetwork.central.dras.aop;

import static net.solarnetwork.central.dras.biz.Notifications.*;

import java.util.LinkedHashMap;
import java.util.Map;

import net.solarnetwork.central.domain.Entity;
import net.solarnetwork.central.dras.dao.UserDao;
import net.solarnetwork.central.dras.domain.EffectiveCollection;
import net.solarnetwork.central.dras.domain.Member;

import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.AfterReturning;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Pointcut;
import org.osgi.service.event.EventAdmin;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;

/**
 * Aspect for publishing OSGi Event Admin events.
 * 
 * @author matt
 * @version $Revision$
 */
@Aspect
public class EntityChangeNotificationAspect extends SecurityAspectSupport {

    private final Logger log = LoggerFactory.getLogger(getClass());

    private EventAdmin eventAdmin;

    /**
     * Constructor.
     * 
     * @param alertBiz the AlertBiz
     */
    @Autowired
    public EntityChangeNotificationAspect(EventAdmin eventAdmin, UserDao userDao) {
        super(userDao);
        this.eventAdmin = eventAdmin;
    }

    @Pointcut(value = "bean(aop*) && execution(* net.solarnetwork.central.dras.biz.*AdminBiz.*(..))")
    public void eventModify() {
    }

    /**
     * Post an OSGi Event when a DRAS entity is created or modified.
     * 
     * @param jp the JoinPoint
     * @param input the DRAS entity input
     * @param output the DRAS entity output
     */
    @AfterReturning(value = "eventModify() && args(input)", returning = "output")
    public void eventUpdate(JoinPoint jp, Entity<Long> input, Entity<Long> output) {
        Map<String, Object> props = createEntityProps(output,
                (input.getId() == null ? EntityChangeType.Created : EntityChangeType.Modified));
        props.put(SERVICE_CLASS_NAME, getServiceClassName(jp));
        postEvent(TOPIC_ENTITY_UPDATE, props);
    }

    /**
     * Post an OSGi Event when a DRAS entity's membership is modified.
     * 
     * @param jp the JoinPoint
     * @param output the DRAS EffectiveCollection
     */
    @AfterReturning(value = "eventModify()", returning = "output")
    public void eventUpdateNotification(JoinPoint jp, EffectiveCollection<? extends Entity<Long>, Member> output) {
        if (output.getEffective() == null) {
            // the membership didn't actually change, so don't post notification
            log.debug("{} membership unchanged, not posting OSGi Event", output.getObject().getClass().getName());
            return;
        }
        Map<String, Object> props = createEntityProps(output.getObject(), EntityChangeType.MembershipUpdated);
        props.put(SERVICE_CLASS_NAME, getServiceClassName(jp));
        postEvent(TOPIC_ENTITY_UPDATE, props);
    }

    private void postEvent(String topicName, Map<String, Object> props) {
        log.debug("Posting OSGi Event {} with props {}", topicName, props);
        org.osgi.service.event.Event note = new org.osgi.service.event.Event(topicName, props);
        this.eventAdmin.postEvent(note);
    }

    private Map<String, Object> createEntityProps(Entity<Long> entity, EntityChangeType change) {
        Map<String, Object> props = new LinkedHashMap<String, Object>();
        props.put(ENTITY_IDENTITY, entity.getId());
        props.put(ENTITY_CLASS_NAME, entity.getClass().getName());
        props.put(ENTITY_CHANGE_TYPE, change.toString());
        props.put(ACTING_USER_IDENTITY, getCurrentUserId());
        return props;
    }

    private String getServiceClassName(JoinPoint jp) {
        Class<?> targetClass = jp.getTarget().getClass();
        Class<?>[] interfaces = targetClass.getInterfaces();
        String className;
        if (interfaces != null && interfaces.length > 0) {
            className = interfaces[0].getName();
        } else {
            className = targetClass.getName();
        }
        return className;
    }

}