001package 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 024import org.apache.fulcrum.parser.ParameterParser; 025import org.apache.turbine.modules.Screen; 026import org.apache.turbine.pipeline.PipelineData; 027import org.apache.turbine.util.RunData; 028import org.apache.turbine.util.uri.TurbineURI; 029 030/** 031 * Users will get this screen if the screen on their browser is in an 032 * invalid state. For example, if they hit "Back" or "Reload" and 033 * then try to submit old form data. 034 * 035 * If you want one of your screens to check for invalid state 036 * then add a hidden form field called "_session_access_counter" 037 * with the value currently stored in the session. The 038 * SessionValidator action will check to see if it is an old 039 * value and redirect you to this screen. 040 * 041 * @author <a href="mailto:mbryson@mont.mindspring.com">Dave Bryson</a> 042 * @author <a href="mailto:hps@intermeta.de">Henning P. Schmiedehausen</a> 043 * @author <a href="mailto:peter@courcoux.biz">Peter Courcoux</a> 044 * @version $Id$ 045 */ 046public class InvalidState implements Screen 047{ 048 /** 049 * Build the Screen. 050 * 051 * @param pipelineData Turbine information. 052 * @throws Exception a generic exception. 053 */ 054 @Override 055 public String doBuild(PipelineData pipelineData) 056 throws Exception 057 { 058 RunData data = pipelineData.getRunData(); 059 StringBuilder body = new StringBuilder(); 060 body.append("<body>"); 061 062 StringBuilder message = new StringBuilder(); 063 StringBuilder sb = new StringBuilder(); 064 sb.append("<b>There has been an error.</b>") 065 .append("<p>") 066 .append("- If you used the browser \"Back\" or \"Reload\"") 067 .append(" buttons please use the navigation buttons we provide") 068 .append(" within the screen.") 069 .append("<p>") 070 .append("Please click "); 071 072 message.append(sb.toString()); 073 ParameterParser pp; 074 pp = (ParameterParser) data.getUser().getTemp("prev_parameters"); 075 pp.remove("_session_access_counter"); 076 077 TurbineURI back = new TurbineURI(data,(String) data.getUser().getTemp("prev_screen")); 078 back.addPathInfo(pp); 079 message.append( "<a href=\"" ).append(back.getRelativeLink()).append("\">here</a>"); 080 message.append(" to return the the screen you were working on."); 081 082 body.append(message); 083 body.append("</body>"); 084 return body.toString(); 085 } 086}