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 java.io.IOException;
018    
019    import org.apache.hivemind.util.PropertyUtils;
020    import org.apache.tapestry.IPage;
021    import org.apache.tapestry.IRequestCycle;
022    import org.apache.tapestry.StaleLinkException;
023    import org.apache.tapestry.services.ResponseRenderer;
024    
025    /**
026     * Implementation of {@link org.apache.tapestry.error.StaleLinkExceptionPresenter} that uses a page
027     * to present the exception. The page must implement a property named "message" of type String and
028     * should present that message to the user.
029     * 
030     * @author Howard M. Lewis Ship
031     * @since 4.0
032     */
033    public class StaleLinkExceptionPresenterImpl implements StaleLinkExceptionPresenter
034    {
035        private ResponseRenderer _responseRenderer;
036    
037        private String _pageName;
038    
039        public void presentStaleLinkException(IRequestCycle cycle, StaleLinkException cause)
040                throws IOException
041        {
042            IPage exceptionPage = cycle.getPage(_pageName);
043    
044            PropertyUtils.write(exceptionPage, "message", cause.getMessage());
045    
046            cycle.activate(exceptionPage);
047    
048            _responseRenderer.renderResponse(cycle);
049        }
050    
051        public void setPageName(String pageName)
052        {
053            _pageName = pageName;
054        }
055    
056        public void setResponseRenderer(ResponseRenderer responseRenderer)
057        {
058            _responseRenderer = responseRenderer;
059        }
060    
061    }