001    package org.apache.turbine.modules.screens.error;
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 org.apache.ecs.ConcreteElement;
025    import org.apache.ecs.ElementContainer;
026    
027    import org.apache.ecs.html.A;
028    import org.apache.fulcrum.parser.ParameterParser;
029    
030    import org.apache.turbine.modules.Screen;
031    import org.apache.turbine.pipeline.PipelineData;
032    import org.apache.turbine.util.RunData;
033    import org.apache.turbine.util.uri.TurbineURI;
034    
035    /**
036     * Users will get this screen if the screen on their browser is in an
037     * invalid state.  For example, if they hit "Back" or "Reload" and
038     * then try to submit old form data.
039     *
040     * If you want one of your screens to check for invalid state
041     * then add a hidden form field called "_session_access_counter"
042     * with the value currently stored in the session.  The
043     * SessionValidator action will check to see if it is an old
044     * value and redirect you to this screen.
045     *
046     * @author <a href="mailto:mbryson@mont.mindspring.com">Dave Bryson</a>
047     * @author <a href="mailto:hps@intermeta.de">Henning P. Schmiedehausen</a>
048     * @author <a href="mailto:peter@courcoux.biz">Peter Courcoux</a>
049     * @version $Id: InvalidState.java 717934 2008-11-15 21:48:47Z tv $
050     */
051    public class InvalidState
052        extends Screen
053    {
054        /**
055         * Build the Screen.
056         *
057         * @param data Turbine information.
058         * @exception Exception, a generic exception.
059         */
060        public ConcreteElement doBuild(RunData data)
061                throws Exception
062        {
063            ElementContainer body = new ElementContainer();
064            ElementContainer message = new ElementContainer();
065    
066            StringBuffer sb = new StringBuffer();
067            sb.append("<b>There has been an error.</b>")
068                    .append("<p>")
069                    .append("- If you used the browser \"Back\" or \"Reload\"")
070                    .append(" buttons please use the navigation buttons we provide")
071                    .append(" within the screen.")
072                    .append("<p>")
073                    .append("Please click ");
074    
075            message.addElement(sb.toString());
076            ParameterParser pp;
077            pp = (ParameterParser) data.getUser().getTemp("prev_parameters");
078            pp.remove("_session_access_counter");
079    
080            TurbineURI back = new TurbineURI(data,(String) data.getUser().getTemp("prev_screen"));
081            back.addPathInfo(pp);
082            message.addElement(new A().setHref(back.getRelativeLink()).addElement("here"));
083    
084            message.addElement(" to return the the screen you were working on.");
085    
086            body.addElement(message);
087            return body;
088        }
089    
090        /**
091         * Build the Screen.
092         *
093         * @param pipelineData Turbine information.
094         * @exception Exception, a generic exception.
095         */
096        public ConcreteElement doBuild(PipelineData pipelineData)
097                throws Exception
098        {
099            RunData data = getRunData(pipelineData);
100            return doBuild(data);
101        }
102    
103    }