src/java/org/apache/turbine/services/TurbineBaseService.java

package org.apache.turbine.services;

/* ====================================================================
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 2001-2003 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 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 end-user documentation included with the redistribution,
 *    if any, must include the following acknowledgment:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowledgment may appear in the software itself,
 *    if and wherever such third-party acknowledgments normally appear.
 *
 * 4. The names "Apache" and "Apache Software Foundation" and
 *    "Apache Turbine" must not be used to endorse or promote products
 *    derived from this software without prior written permission. For
 *    written permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache",
 *    "Apache Turbine", nor may "Apache" appear in their name, without
 *    prior written permission of the Apache Software Foundation.
 *
 * 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.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 */

import javax.servlet.ServletConfig;

import org.apache.turbine.pipeline.PipelineData;
import org.apache.turbine.util.RunData;

/**
 * <p>This class provides a <code>Service</code> implementation that
 * Services used in Turbine are required to extend.  The
 * functionality provided in addition to <code>BaseService</code>
 * functionality is recognizing objects used in early initialization
 * of <code>Services</code> in Turbine, and passing them to
 * appropriate convenience methods.  These methods should be overriden
 * to provide desired initialization functionality.</p>
 *
 * <p><strong>Note!</strong><br>Remember to call
 * <code>setInit(true)</code> after successful initialization.</p>
 *
 * <p><strong>Note!</strong><br>If you need to use another
 * <code>Service</code> inside your early initialization, remember to
 * request initialization of that <code>Service</code> before using
 * it:</p>
 *
 * <pre><code>
 * getServiceBroker().initClass("OtherService",data);
 * OtherService service =
 *         (OtherService)getServiceBroker().getService("OtherService");
 * </code></pre>
 *
 * @author <a href="mailto:greg@shwoop.com">Greg Ritter</a>
 * @author <a href="mailto:bmclaugh@algx.net">Brett McLaughlin</a>
 * @author <a href="mailto:burton@apache.org">Kevin Burton</a>
 * @author <a href="mailto:krzewski@e-point.pl">Rafal Krzewski</a>
 * @author <a href="mailto:jon@latchkey.com">Jon S. Stevens</a>
 * @author <a href="mailto:jvanzyl@periapt.com">Jason van Zyl</a>
 * @author <a href="mailto:peter@courcoux.biz">Peter Courcoux</a>
 * @version $Id$
 */
public abstract class TurbineBaseService
        extends BaseService
{
    /**
     * Performs early initialization.  Overrides init() method in
     * BaseService to detect objects used in Turbine's Service
     * initialization and pass them to apropriate init() methods.
     *
     * @param data An Object to use for initialization activities.
     * @exception InitializationException if initialization of this
     * class was not successful.
     */
    public void init(Object data)
            throws InitializationException
    {
        if (data instanceof ServletConfig)
        {
            init((ServletConfig) data);
        }
        else if (data instanceof RunData)
        {
            init((RunData) data);
        }
        else if (data instanceof PipelineData)
        {
            init((PipelineData) data);
        }
    }

    /**
     * Performs early initialization.
     *
     * @param config A ServletConfing to use for initialization
     * activities.
     * @exception InitializationException if initialization of this
     * class was not successful.
     * @deprecated Use init() instead
     */
    public void init(ServletConfig config) throws InitializationException
    {
    }

    /**
     * Performs early initialization.
     *
     * @deprecated Use the PipelineData version instead.
     * @param data An RunData to use for initialization activities.
     * @exception InitializationException if initialization of this
     * class was not successful.
     */
    public void init(RunData data) throws InitializationException
    {
    }

    /**
     * Performs early initialization.
     *
     * @param data A PipelineData to use for initialization activities.
     * @exception InitializationException if initialization of this
     * class was not successful.
     */
    public void init(PipelineData data) throws InitializationException
    {
    }

    
    /**
     * Performs late initialization.
     *
     * If your class relies on early initialization, and the object it
     * expects was not received, you can use late initialization to
     * throw an exception and complain.
     *
     * @exception InitializationException, if initialization of this
     * class was not successful.
     */
    public void init() throws InitializationException
    {
        setInit(true);
    }

    /**
     * Returns to uninitialized state.
     *
     * You can use this method to release resources thet your Service
     * allocated when Turbine shuts down.
     */
    public void shutdown()
    {
        setInit(false);
    }
}