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.web;
016    
017    import java.io.IOException;
018    import java.io.OutputStream;
019    import java.io.PrintWriter;
020    
021    import javax.servlet.http.HttpServletResponse;
022    
023    import org.apache.commons.logging.Log;
024    import org.apache.commons.logging.LogFactory;
025    import org.apache.hivemind.ApplicationRuntimeException;
026    import org.apache.hivemind.util.Defense;
027    import org.apache.tapestry.util.ContentType;
028    
029    /**
030     * Adapts {@link javax.servlet.http.HttpServletResponse} as
031     * {@link org.apache.tapestry.web.WebResponse}.
032     * 
033     * @author Howard M. Lewis Ship
034     * @since 4.0
035     */
036    public class ServletWebResponse implements WebResponse
037    {
038        private static final Log LOG = LogFactory.getLog(ServletWebResponse.class);
039    
040        private final HttpServletResponse _servletResponse;
041    
042        private boolean _needsReset;
043    
044        public ServletWebResponse(HttpServletResponse response)
045        {
046            Defense.notNull(response, "response");
047    
048            _servletResponse = response;
049        }
050    
051        public OutputStream getOutputStream(ContentType contentType)
052        {
053            Defense.notNull(contentType, "contentType");
054    
055            _servletResponse.setContentType(contentType.getMimeType());
056    
057            try
058            {
059                return _servletResponse.getOutputStream();
060            }
061            catch (IOException ex)
062            {
063                throw new ApplicationRuntimeException(WebMessages.streamOpenError(contentType, ex),
064                        null, ex);
065            }
066        }
067    
068        public PrintWriter getPrintWriter(ContentType contentType) throws IOException
069        {
070            Defense.notNull(contentType, "contentType");
071    
072            if (_needsReset)
073                reset();
074    
075            _needsReset = true;
076    
077            _servletResponse.setContentType(contentType.toString());
078    
079            try
080            {
081                return _servletResponse.getWriter();
082            }
083            catch (IOException ex)
084            {
085                throw new ApplicationRuntimeException(WebMessages.writerOpenError(contentType, ex),
086                        null, ex);
087            }
088        }
089    
090        public String encodeURL(String url)
091        {
092            return _servletResponse.encodeURL(url);
093        }
094    
095        public void reset()
096        {
097            try
098            {
099                _servletResponse.reset();
100            }
101            catch (IllegalStateException ex)
102            {
103                LOG.error(WebMessages.resetFailed(ex), ex);
104            }
105        }
106    
107        public void setContentLength(int length)
108        {
109            _servletResponse.setContentLength(length);
110        }
111    
112        public String getNamespace()
113        {
114            return "";
115        }
116    
117        public void setDateHeader(String name, long date)
118        {
119            _servletResponse.setDateHeader(name, date);
120        }
121    
122        public void setStatus(int status)
123        {
124            _servletResponse.setStatus(status);
125        }
126    
127        public void setHeader(String name, String value)
128        {
129            _servletResponse.setHeader(name, value);
130        }
131    
132        public void setIntHeader(String name, int value)
133        {
134            _servletResponse.setIntHeader(name, value);
135        }
136    
137        public void sendError(int statusCode, String message) throws IOException
138        {
139            _servletResponse.sendError(statusCode, message);
140        }
141    
142    }