com.ideabase.repository.core.aspect.DataAccessEventAdvice.java Source code

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Here is the source code for com.ideabase.repository.core.aspect.DataAccessEventAdvice.java

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/* $Id: DataAccessEventAdvice.java 249 2007-12-02 08:32:47Z hasan $ */
/*
 ******************************************************************************
 *   Copyright (C) 2007 IDEASense, (hasin & hasan) 
 *
 *   This library is free software; you can redistribute it and/or
 *   modify it under the terms of the GNU Lesser General Public
 *   License as published by the Free Software Foundation; either
 *   version 2.1 of the License, or (at your option) any later version.
 *
 *   This library 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
 *   Lesser General Public License for more details.
 *
 *   You should have received a copy of the GNU Lesser General Public
 *   License along with this library; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 ******************************************************************************
 * $LastChangedBy: hasan $
 * $LastChangedDate: 2007-12-02 14:32:47 +0600 (Sun, 02 Dec 2007) $
 * $LastChangedRevision: 249 $
 ******************************************************************************
*/
package com.ideabase.repository.core.aspect;

import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.AfterReturning;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.Signature;
import com.ideabase.repository.api.EventManager;
import com.ideabase.repository.api.event.Event;
import com.ideabase.repository.core.dao.ItemDAO;
import com.ideabase.repository.core.dao.ItemMappingDAO;
import com.ideabase.repository.core.dao.Item;
import com.ideabase.repository.core.dao.ItemMapping;

import static com.ideabase.repository.api.event.Event.EventType;

/**
 *
 * @author <a href="mailto:hasan@somewherein.net">nhm tanveer hossain khan
 *        (hasan)</a>
 */
@Aspect
public class DataAccessEventAdvice {
    private final EventManager mEventManager;
    private static final String METHOD_PREFIX_CREATE = "create";
    private static final String METHOD_PREFIX_UPDATE = "update";
    private static final String METHOD_PREFIX_DELETE = "delete";

    public DataAccessEventAdvice(final EventManager pEventManager) {
        mEventManager = pEventManager;
    }

    @AfterReturning(pointcut = "com.ideabase.repository.core.aspect.ArchitecturePointcuts.dataAccessOperation()", returning = "pReturnValue")
    public void publishSaveEvent(final Object pReturnValue) {
        //TODO: System.out.println("Return value - " + pReturnValue);
    }

    /**
     * Find Signature class. now publish event based on the specific class and
     * method signature.
     */
    @Around("com.ideabase.repository.core.aspect.ArchitecturePointcuts.dataAccessOperation()")
    public Object aroundOperation(final ProceedingJoinPoint pProceedingJoinPoint) throws Throwable {
        // Determine source class and mehtod.
        final Signature signature = pProceedingJoinPoint.getSignature();
        final Class signatureClass = signature.getDeclaringType();
        final String signatureMethod = signature.getName();
        final Object[] arguments = pProceedingJoinPoint.getArgs();

        // Execute the operation
        final Object returned = pProceedingJoinPoint.proceed();

        // publish event
        addEvent(returned, signatureClass, signatureMethod, arguments);

        // Return the executed output.
        return returned;
    }

    private void addEvent(final Object pReturned, final Class pSignatureClass, final String pSignatureMethod,
            final Object[] pArguments) {
        if (pSignatureClass == ItemDAO.class || pSignatureClass == ItemMappingDAO.class) {
            handleDAOEvent(pReturned, pSignatureClass, pSignatureMethod, pArguments);
        }
    }

    private void handleDAOEvent(final Object pReturned, final Class pSignatureClass, final String pSignatureMethod,
            final Object[] pArguments) {
        // Create item method
        if (pSignatureMethod.startsWith(METHOD_PREFIX_CREATE)) {
            // publish the events
            mEventManager.publishEvent(newEvent((Integer) pReturned, EventType.ITEM_CREATED, pSignatureClass));
        }
        // update item
        else if (pSignatureMethod.startsWith(METHOD_PREFIX_UPDATE)) {
            mEventManager.publishEvent(newEvent((Integer) pReturned, EventType.ITEM_UPDATED, pSignatureClass));
        }
        // delete item
        else if (pSignatureMethod.startsWith(METHOD_PREFIX_DELETE)) {
            final Integer itemId;
            if (pArguments[0] instanceof Item) {
                itemId = ((Item) pArguments[0]).getId();
            } else if (pArguments[0] instanceof ItemMapping) {
                itemId = ((ItemMapping) pArguments[0]).getLeftId();
            } else {
                itemId = null;
            }
            mEventManager.publishEvent(newEvent(itemId, EventType.ITEM_DELETED, pSignatureClass));
        }
    }

    private Event newEvent(final Integer pItemId, final EventType pEventType, final Class pSource) {
        return new Event(pItemId, pEventType, pSource);
    }
}