001    package org.apache.myfaces.tobago.util;
002    
003    /*
004     * Licensed to the Apache Software Foundation (ASF) under one or more
005     * contributor license agreements.  See the NOTICE file distributed with
006     * this work for additional information regarding copyright ownership.
007     * The ASF licenses this file to You under the Apache License, Version 2.0
008     * (the "License"); you may not use this file except in compliance with
009     * the License.  You may obtain a copy of the License at
010     *
011     *      http://www.apache.org/licenses/LICENSE-2.0
012     *
013     * Unless required by applicable law or agreed to in writing, software
014     * distributed under the License is distributed on an "AS IS" BASIS,
015     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
016     * See the License for the specific language governing permissions and
017     * limitations under the License.
018     */
019    
020    import org.apache.myfaces.tobago.context.ClientProperties;
021    
022    import javax.faces.context.ExternalContext;
023    import javax.faces.context.FacesContext;
024    import javax.servlet.http.HttpServletResponse;
025    
026    /*
027     * Date: Oct 21, 2006
028     * Time: 10:39:25 AM
029     */
030    public class ResponseUtils {
031    
032      public static void ensureNoCacheHeader(ExternalContext externalContext) {
033        // TODO PortletRequest
034        if (externalContext.getResponse() instanceof HttpServletResponse) {
035          HttpServletResponse response = (HttpServletResponse) externalContext.getResponse();
036          response.setHeader("Cache-Control", "no-cache,no-store,max-age=0,must-revalidate");
037          response.setHeader("Pragma", "no-cache");
038          response.setDateHeader("Expires", 0);
039          response.setDateHeader("max-age", 0);
040        }
041      }
042    
043      public static void ensureContentTypeHeader(FacesContext facesContext, String charset) {
044        // TODO PortletRequest
045        if (facesContext.getExternalContext().getResponse() instanceof HttpServletResponse) {
046          HttpServletResponse response = (HttpServletResponse) facesContext.getExternalContext().getResponse();
047          response.setContentType(generateContentType(facesContext, charset));
048        }
049      }
050    
051      private static String generateContentType(FacesContext facesContext, String charset) {
052        StringBuilder sb = new StringBuilder("text/");
053        ClientProperties clientProperties
054            = ClientProperties.getInstance(facesContext.getViewRoot());
055        sb.append(clientProperties.getContentType());
056        if (charset == null) {
057          charset = "UTF-8";
058        }
059        sb.append("; charset=");
060        sb.append(charset);
061        return sb.toString();
062      }
063    }