    001package org.apache.turbine.modules.actions;
    002
    003/*
    004 * Licensed to the Apache Software Foundation (ASF) under one
    005 * or more contributor license agreements.  See the NOTICE file
    006 * distributed with this work for additional information
    007 * regarding copyright ownership.  The ASF licenses this file
    008 * to you under the Apache License, Version 2.0 (the
    009 * "License"); you may not use this file except in compliance
    010 * with the License.  You may obtain a copy of the License at
    011 *
    012 *   http://www.apache.org/licenses/LICENSE-2.0
    013 *
    014 * Unless required by applicable law or agreed to in writing,
    015 * software distributed under the License is distributed on an
    016 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
    017 * KIND, either express or implied.  See the License for the
    018 * specific language governing permissions and limitations
    019 * under the License.
    020 */
    021
    022import org.apache.turbine.modules.screens.TemplateScreen;
    023import org.apache.turbine.pipeline.PipelineData;
    024import org.apache.turbine.util.velocity.VelocityActionEvent;
    025import org.apache.velocity.context.Context;
    026
    027/**
    028 * This class provides a convenience methods for Velocity Actions to use. Since
    029 * this class is abstract, it should only be extended and not used directly.
    030 *
    031 * @author <a href="mailto:jon@latchkey.com">Jon S. Stevens</a>
    032 * @author <a href="mailto:jvanzyl@periapt.com">Jason van Zyl</a>
    033 * @author <a href="mailto:peter@courcoux.biz">Peter Courcoux</a>
    034 * @version $Id: VelocityAction.java 1706425 2015-10-02 14:47:51Z tv $
    035 */
    036public abstract class VelocityAction extends VelocityActionEvent
    037{
    038    /**
    039     * Initialize the module.
    040     *
    041     * @throws Exception a generic exception.
    042     */
    043    @Override
    044    public void initialize() throws Exception
    045    {
    046        initialized = true;
    047    }
    048
    049    /**
    050     * You SHOULD override this method and implement it in your action.
    051     *
    052     * @param pipelineData Turbine information.
    053     * @param context Context for web pages.
    054     * @throws Exception a generic exception.
    055     */
    056    public abstract void doPerform(PipelineData pipelineData, Context context)
    057            throws Exception;
    058
    059    /**
    060     * Sets up the context and then calls super.perform(); thus, subclasses
    061     * don't have to worry about getting a context themselves! If a subclass
    062     * throws an exception then depending on whether
    063     * action.event.bubbleexception is true, then it bubbles it farther up, or
    064     * traps it there.
    065     *
    066     * @param pipelineData Turbine information.
    067     * @throws Exception a generic exception.
    068     */
    069    @Override
    070    protected void perform(PipelineData pipelineData) throws Exception
    071    {
    072        try
    073        {
    074            super.perform(pipelineData);
    075        }
    076        catch (Exception e)
    077        {
    078            if (bubbleUpException)
    079            {
    080                throw e;
    081            }
    082        }
    083    }
    084
    085    /**
    086     * This method is used when you want to short circuit an Action and change
    087     * the template that will be executed next.
    088     *
    089     * @param pipelineData Turbine information.
    090     * @param template The template that will be executed next.
    091     */
    092    public void setTemplate(PipelineData pipelineData, String template)
    093    {
    094        TemplateScreen.setTemplate(pipelineData, template);
    095    }
    096}