    001    package org.apache.turbine.pipeline;
    002
    003
    004    /*
    005     * Licensed to the Apache Software Foundation (ASF) under one
    006     * or more contributor license agreements.  See the NOTICE file
    007     * distributed with this work for additional information
    008     * regarding copyright ownership.  The ASF licenses this file
    009     * to you under the Apache License, Version 2.0 (the
    010     * "License"); you may not use this file except in compliance
    011     * with the License.  You may obtain a copy of the License at
    012     *
    013     *   http://www.apache.org/licenses/LICENSE-2.0
    014     *
    015     * Unless required by applicable law or agreed to in writing,
    016     * software distributed under the License is distributed on an
    017     * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
    018     * KIND, either express or implied.  See the License for the
    019     * specific language governing permissions and limitations
    020     * under the License.
    021     */
    022
    023
    024    import java.io.IOException;
    025
    026    import org.apache.commons.logging.Log;
    027    import org.apache.commons.logging.LogFactory;
    028    import org.apache.turbine.util.RunData;
    029    import org.apache.turbine.util.TurbineException;
    030    import org.apache.turbine.util.uri.URIConstants;
    031
    032    /**
    033     * This valve is responsible for setting the 'action' property of RunData based
    034     * on request parameter. There is no default action, since a null action is
    035     * perfectly valid.
    036     *
    037     * @author <a href="mailto:james@jamestaylor.org">James Taylor</a>
    038     * @author <a href="mailto:peter@courcoux.biz">Peter Courcoux</a>
    039     */
    040    public class DetermineActionValve
    041        extends AbstractValve
    042    {
    043        private static final Log log
    044            = LogFactory.getLog(DetermineActionValve.class);
    045
    046        /**
    047         * @see org.apache.turbine.Valve#invoke(RunData, ValveContext)
    048         */
    049        public void invoke(PipelineData pipelineData, ValveContext context)
    050            throws IOException, TurbineException
    051        {
    052            RunData data = getRunData(pipelineData);
    053            if (! data.hasAction())
    054            {
    055                String action =
    056                    data.getParameters().getString(URIConstants.CGI_ACTION_PARAM);
    057
    058                if (action != null)
    059                {
    060                    data.setAction(action);
    061
    062                    log.debug("Set action from request parameter");
    063                }
    064                else
    065                {
    066                    log.debug("No action");
    067                }
    068            }
    069
    070            if (log.isDebugEnabled())
    071            {
    072                log.debug("Action is now: " + data.getAction());
    073            }
    074
    075            // Pass control to the next Valve in the Pipeline
    076            context.invokeNext(pipelineData);
    077        }
    078    }