AbstractInterceptor.java :  » J2EE » Jaffa » org » jaffa » persistence » engines » jdbcengine » interceptor » Java Open Source

Java Open Source » J2EE » Jaffa 
Jaffa » org » jaffa » persistence » engines » jdbcengine » interceptor » AbstractInterceptor.java
/*
 * ====================================================================
 * JAFFA - Java Application Framework For All
 *
 * Copyright (C) 2002 JAFFA Development Group
 *
 *     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
 *
 * Redistribution and use of this software and associated documentation ("Software"),
 * with or without modification, are permitted provided that the following conditions are met:
 * 1.  Redistributions of source code must retain copyright statements and notices.
 *         Redistributions must also contain a copy of this document.
 * 2.  Redistributions in binary form must reproduce the above copyright notice,
 *   this list of conditions and the following disclaimer in the documentation
 *   and/or other materials provided with the distribution.
 * 3.  The name "JAFFA" must not be used to endorse or promote products derived from
 *   this Software without prior written permission. For written permission,
 *   please contact mail to: jaffagroup@yahoo.com.
 * 4.  Products derived from this Software may not be called "JAFFA" nor may "JAFFA"
 *   appear in their names without prior written permission.
 * 5.  Due credit should be given to the JAFFA Project (http://jaffa.sourceforge.net).
 *
 * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 */

package org.jaffa.persistence.engines.jdbcengine.interceptor;

import org.jaffa.persistence.engines.jdbcengine.datasource.PersistentTransaction;
import org.jaffa.persistence.exceptions.UOWException;

/** This is the abstract class for an Interceptor. All new interceptors must
 * inherit from this base class. A set of interceptors exists the Engine.
 */
public abstract class AbstractInterceptor {

    /** The next interceptor in the invocation chain */
    private AbstractInterceptor m_next;

    /** Sets the next Interceptor in the chain.
     *@param next the next Interceptor in the chain.
     */
    public void setNextInterceptor(AbstractInterceptor next) {
        m_next = next;
    }

    /** Returns the next Interceptor in the chain. A null will be returned in case this is the end of the chain.
     * @return the next Interceptor in the chain.
     */
    public AbstractInterceptor getNextInterceptor() {
        return m_next;
    }

    /**Performs the actual logic associated with the interceptor.
     * Should contain atomic logic, i.e., does not assumes input or output of other interceptors in the chain.
     * @param pt The PersistentTransaction object, on which the Interceptor is to be executed.
     * @throws UOWException if any error occurs.
     * @return the output from the next Interceptor in the chain.
     */
    public abstract Object invoke(PersistentTransaction pt) throws UOWException;
}
java2s.com  | Contact Us | Privacy Policy
Copyright 2009 - 12 Demo Source and Support. All rights reserved.
All other trademarks are property of their respective owners.