001 // Copyright 2005 The Apache Software Foundation 002 // 003 // Licensed under the Apache License, Version 2.0 (the "License"); 004 // you may not use this file except in compliance with the License. 005 // You may obtain a copy of the License at 006 // 007 // http://www.apache.org/licenses/LICENSE-2.0 008 // 009 // Unless required by applicable law or agreed to in writing, software 010 // distributed under the License is distributed on an "AS IS" BASIS, 011 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 012 // See the License for the specific language governing permissions and 013 // limitations under the License. 014 015 package org.apache.tapestry.error; 016 017 import org.apache.hivemind.ApplicationRuntimeException; 018 import org.apache.tapestry.IPage; 019 import org.apache.tapestry.IRequestCycle; 020 import org.apache.tapestry.StaleLinkException; 021 import org.apache.tapestry.services.ResponseRenderer; 022 023 /** 024 * Implementation of {@link org.apache.tapestry.error.StaleLinkExceptionPresenter} that uses a page 025 * to present the exception. The page must implement a property named "message" of type String and 026 * should present that message to the user. 027 * 028 * @author Howard M. Lewis Ship 029 * @since 4.0 030 */ 031 public class StaleLinkExceptionPresenterImpl implements StaleLinkExceptionPresenter 032 { 033 private RequestExceptionReporter _requestExceptionReporter; 034 035 private ResponseRenderer _responseRenderer; 036 037 private String _pageName; 038 039 public void presentStaleLinkException(IRequestCycle cycle, StaleLinkException cause) 040 { 041 try 042 { 043 IPage exceptionPage = cycle.getPage(_pageName); 044 045 exceptionPage.setProperty("message", cause.getMessage()); 046 047 cycle.activate(exceptionPage); 048 049 _responseRenderer.renderResponse(cycle); 050 } 051 catch (Throwable ex) 052 { 053 // Worst case scenario. The exception page itself is broken, leaving 054 // us with no option but to write the cause to the output. 055 056 _requestExceptionReporter.reportRequestException(ErrorMessages 057 .unableToProcessClientRequest(cause), cause); 058 059 // Also, write the exception thrown when redendering the exception 060 // page, so that can get fixed as well. 061 062 _requestExceptionReporter.reportRequestException(ErrorMessages 063 .unableToPresentExceptionPage(ex), ex); 064 065 // And throw the exception. 066 067 throw new ApplicationRuntimeException(ex.getMessage(), ex); 068 } 069 070 } 071 072 public void setPageName(String pageName) 073 { 074 _pageName = pageName; 075 } 076 077 public void setRequestExceptionReporter(RequestExceptionReporter requestExceptionReporter) 078 { 079 _requestExceptionReporter = requestExceptionReporter; 080 } 081 082 public void setResponseRenderer(ResponseRenderer responseRenderer) 083 { 084 _responseRenderer = responseRenderer; 085 } 086 087 }