package org.apache.turbine.util.velocity;
/* ====================================================================
* The Apache Software License, Version 1.1
*
* Copyright (c) 2001 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 java.lang.reflect.Method;
import java.util.Enumeration;
import org.apache.turbine.modules.ActionEvent;
import org.apache.turbine.services.velocity.VelocityService;
import org.apache.turbine.util.ParameterParser;
import org.apache.turbine.util.RunData;
import org.apache.turbine.util.ValueParser;
import org.apache.turbine.util.template.TemplateInfo;
import org.apache.velocity.context.Context;
/**
* If you are using VelocitySite stuff, then your Action's should
* extend this class instead of extending the ActionEvent class. The
* difference between this class and the ActionEvent class is that
* this class will first attempt to execute one of your doMethod's
* with a constructor like this:
*
* <p>doEvent(RunData data, Context context)
*
* <p>It gets the context from the TemplateInfo.getTemplateContext()
* method. If it can't find a method like that, then it will try to
* execute the method without the Context in it.
*
* @author <a href="mailto:jon@latchkey.com">Jon S. Stevens</a>
* @author <a href="mailto:jvanzyl@periapt.com">Jason van Zyl</a>
* @version $Id: VelocityActionEvent.java,v 1.6.10.4 2001/05/20 15:58:17 jvanzyl Exp $
*/
public abstract class VelocityActionEvent extends ActionEvent
{
/**
* You need to implement this in your classes that extend this
* class.
*
* @param data A Turbine RunData object.
* @exception Exception, a generic exception.
*/
public abstract void doPerform( RunData data )
throws Exception;
/**
* This overrides the default Action.perform() to execute the
* doEvent() method. If that fails, then it will execute the
* doPerform() method instead.
*
* @param data A Turbine RunData object.
* @exception Exception, a generic exception.
*/
protected void perform( RunData data )
throws Exception
{
try
{
executeEvents(data, (Context)data.getTemplateInfo()
.getTemplateContext(VelocityService.CONTEXT));
}
catch (NoSuchMethodException e)
{
doPerform( data );
}
}
/**
* This method should be called to execute the event based system.
*
* @param data A Turbine RunData object.
* @param context Velocity context information.
* @exception Exception, a generic exception.
*/
public void executeEvents(RunData data, Context context) throws Exception
{
// Name of the button.
String theButton = null;
// ParameterParser.
ParameterParser pp = data.getParameters();
String button = pp.convert(BUTTON);
// Loop through and find the button.
for (Enumeration e = pp.keys() ; e.hasMoreElements() ;)
{
String key = (String) e.nextElement();
if (key.startsWith(button))
{
theButton = formatString(key);
break;
}
}
if (theButton == null)
throw new NoSuchMethodException("ActionEvent: The button was null");
try
{
// The arguments to the method to find.
Class[] classes = new Class[2];
classes[0] = RunData.class;
classes[1] = Context.class;
// The arguments to pass to the method to execute.
Object[] args = new Object[2];
Method method = getClass().getMethod(theButton, classes);
args[0] = data;
args[1] = context;
method.invoke(this, args );
}
catch (NoSuchMethodException nsme)
{
// Attempt to execut things the old way..
super.executeEvents(data);
}
}
}