001    /*
002     * Licensed to the Apache Software Foundation (ASF) under one
003     * or more contributor license agreements.  See the NOTICE file
004     * distributed with this work for additional information
005     * regarding copyright ownership.  The ASF licenses this file
006     * to you under the Apache License, Version 2.0 (the
007     * "License"); you may not use this file except in compliance
008     * with the License.  You may obtain a copy of the License at
009     *
010     *   http://www.apache.org/licenses/LICENSE-2.0
011     *
012     * Unless required by applicable law or agreed to in writing,
013     * software distributed under the License is distributed on an
014     * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015     * KIND, either express or implied.  See the License for the
016     * specific language governing permissions and limitations
017     * under the License.
018     */
019    
020    package org.apache.myfaces.tobago.servlet;
021    
022    import org.apache.commons.io.IOUtils;
023    import org.apache.commons.logging.Log;
024    import org.apache.commons.logging.LogFactory;
025    import org.apache.myfaces.tobago.util.MimeTypeUtils;
026    
027    import javax.servlet.ServletConfig;
028    import javax.servlet.ServletException;
029    import javax.servlet.http.HttpServlet;
030    import javax.servlet.http.HttpServletRequest;
031    import javax.servlet.http.HttpServletResponse;
032    import java.io.IOException;
033    import java.io.InputStream;
034    import java.util.Date;
035    
036    /**
037     * <p><pre>
038     * &lt;servlet&gt;
039     *   &lt;servlet-name&gt;ResourceServlet&lt;/servlet-name&gt;
040     *   &lt;servlet-class&gt;org.apache.myfaces.tobago.servlet.ResourceServlet&lt;/servlet-class&gt;
041     *   &lt;init-param&gt;
042     *     &lt;description&gt;The value for the expires header in seconds.
043     *            Default is no expires header.&lt;/description&gt;
044     *     &lt;param-name&gt;expires&lt;/param-name&gt;
045     *     &lt;param-value&gt;14400&lt;/param-value&gt;
046     *   &lt;/init-param&gt;
047     * &lt;/servlet&gt;
048     * &lt;servlet-mapping&gt;
049     *   &lt;servlet-name&gt;ResourceServlet&lt;/servlet-name&gt;
050     *   &lt;url-pattern&gt;/org/apache/myfaces/tobago/renderkit/*&lt;/url-pattern&gt;
051     * &lt;/servlet-mapping&gt;
052     * </pre><p>
053     *
054     * @since 1.0.7
055     */
056    public class ResourceServlet extends HttpServlet {
057    
058      private static final long serialVersionUID = -4491419290205206466L;
059    
060      private static final Log LOG = LogFactory.getLog(ResourceServlet.class);
061    
062      private Long expires;
063    
064      @Override
065      public void init(ServletConfig servletConfig) throws ServletException {
066        super.init(servletConfig);
067        String expiresString = servletConfig.getInitParameter("expires");
068    
069        expires = null;
070        if (expiresString != null) {
071          try {
072            expires = new Long(expiresString);
073          } catch (NumberFormatException e) {
074            LOG.error("Caught: " + e.getMessage(), e);
075          }
076        }
077      }
078    
079      @Override
080      protected void service(
081          HttpServletRequest request, HttpServletResponse response)
082          throws ServletException, IOException {
083    
084        String requestURI = request.getRequestURI();
085        String resource = requestURI.substring(request.getContextPath().length() + 1);
086    
087        if (expires != null) {
088          response.setHeader("Cache-Control", "max-age=" + expires);
089          response.setDateHeader("Expires", new Date().getTime() + (expires * 1000));
090        }
091        String contentType = MimeTypeUtils.getMimeTypeForFile(requestURI);
092        if (contentType != null) {
093          response.setContentType(contentType);
094        } else {
095          String message = "Unsupported mime type of resource='" + resource + "'";
096          LOG.warn(message + " (because of security reasons)");
097          response.sendError(HttpServletResponse.SC_FORBIDDEN, message);
098          return;
099        }
100    
101        InputStream inputStream = null;
102        try {
103          ClassLoader classLoader = Thread.currentThread().getContextClassLoader();
104    
105          // meta inf (like in servlet 3.0)
106          inputStream = classLoader.getResourceAsStream("META-INF/resources/" + resource);
107    
108          // "normal" classpath
109          if (inputStream == null) {
110            inputStream = classLoader.getResourceAsStream(resource);
111          }
112    
113          if (inputStream != null) {
114            IOUtils.copy(inputStream, response.getOutputStream());
115          } else {
116            String message = "Resource '" + resource + "' not found!";
117            LOG.warn(message);
118            response.sendError(HttpServletResponse.SC_NOT_FOUND, message);
119          }
120        } finally {
121          IOUtils.closeQuietly(inputStream);
122        }
123      }
124    }