ChangeArgumentPreprocessor.java

/**
 *   GRANITE DATA SERVICES
 *   Copyright (C) 2006-2015 GRANITE DATA SERVICES S.A.S.
 *
 *   This file is part of the Granite Data Services Platform.
 *
 *                               ***
 *
 *   Community License: GPL 3.0
 *
 *   This file 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 3 of the License,
 *   or (at your option) any later version.
 *
 *   This file 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, see <http://www.gnu.org/licenses/>.
 *
 *                               ***
 *
 *   Available Commercial License: GraniteDS SLA 1.0
 *
 *   This is the appropriate option if you are creating proprietary
 *   applications and you are not prepared to distribute and share the
 *   source code of your application under the GPL v3 license.
 *
 *   Please visit http://www.granitedataservices.com/license for more
 *   details.
 */
package org.granite.client.tide.data;

import java.lang.annotation.Annotation;
import java.lang.reflect.Method;

import org.granite.client.persistence.Lazy;
import org.granite.client.tide.data.impl.ObjectUtil;
import org.granite.client.tide.server.ArgumentPreprocessor;
import org.granite.client.tide.server.ServerSession;
import org.granite.logging.Logger;

public class ChangeArgumentPreprocessor implements ArgumentPreprocessor {

    private final static Logger log = Logger.getLogger(ChangeArgumentPreprocessor.class);
    
    public Object[] preprocess(ServerSession serverSession, Method method, Object[] args) {
        if (method == null)
            return args;
        
        EntityManager entityManager = null;
        ChangeSetBuilder csb = null;
        
        for (int idx = 0; idx < args.length; idx++) {
    		Annotation[] annotations = method.getParameterAnnotations()[idx];
    		if (annotations == null)
    			continue;
    		boolean found = false;
    		for (Annotation annotation : annotations) {
    			if (annotation.annotationType().equals(Lazy.class)) {
    				found = true;
    				break;
    			}
    		}
    		if (!found)
    			continue;
    		
    		Object entity = args[idx];
    		if (entity == null)
    			continue;
    		
    		if (entityManager == null) {
    			entityManager = PersistenceManager.getEntityManager(entity);
    			csb = new ChangeSetBuilder(entityManager, serverSession);
    		}
    		else if (PersistenceManager.getEntityManager(entity) != entityManager) {
    			throw new IllegalArgumentException("All arguments passed to remote call must be in the same entity manager");
    		}
    		
    		if (entityManager != null && entityManager.getDataManager().hasVersionProperty(entity) && entityManager.getDataManager().getVersion(entity) != null) {
            	log.debug("Building ChangeSet for argument %d: %s", idx, ObjectUtil.toString(entity));
                args[idx] = csb.buildEntityChangeSet(entity);
            }
        }
        return args;
    }
}