1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one 3 * or more contributor license agreements. See the NOTICE file 4 * distributed with this work for additional information 5 * regarding copyright ownership. The ASF licenses this file 6 * to you under the Apache License, Version 2.0 (the 7 * "License"); you may not use this file except in compliance 8 * with the License. You may obtain a copy of the License at 9 * 10 * http://www.apache.org/licenses/LICENSE-2.0 11 * 12 * Unless required by applicable law or agreed to in writing, 13 * software distributed under the License is distributed on an 14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 15 * KIND, either express or implied. See the License for the 16 * specific language governing permissions and limitations 17 * under the License. 18 */ 19 package org.apache.myfaces.orchestra.requestParameterProvider.jsf; 20 21 import org.apache.myfaces.orchestra.requestParameterProvider.RequestParameterResponseWrapper; 22 import org.apache.myfaces.orchestra.requestParameterProvider.RequestParameterServletFilter; 23 24 import javax.faces.FacesException; 25 import javax.faces.context.FacesContext; 26 import javax.faces.context.FacesContextFactory; 27 import javax.faces.lifecycle.Lifecycle; 28 import javax.servlet.http.HttpServletRequest; 29 import javax.servlet.http.HttpServletResponse; 30 31 /** 32 * Ensure that a custom wrapper is put around the HttpServletResponse so that encodeURL can be 33 * intercepted and modified. 34 * <p> 35 * There is a servlet filter (RequestParameterServletFilter) that does this in the obvious way, but 36 * it is a nuisance to have to set up filters in the web.xml. This class implements a sneaky hack 37 * to get this to happen automatically for JSF applications, ie no servlet filter is needed when 38 * this is specified in the faces-config.xml file as the FacesContextFactory. 39 * <p> 40 * If you have to deal with a mixed environment e.g. JSP/JSF it would be better to use the 41 * {@link org.apache.myfaces.orchestra.requestParameterProvider.RequestParameterServletFilter}. 42 */ 43 public class RequestParameterFacesContextFactory extends FacesContextFactory 44 { 45 private final FacesContextFactory original; 46 47 public RequestParameterFacesContextFactory(FacesContextFactory original) 48 { 49 this.original = original; 50 } 51 52 /** 53 * Invokes the getFacesContext method on the original factory in order to return a 54 * perfectly normal FacesContext instance. However the ServletResponse object passed 55 * to that FacesContext instance is a modified one that tweaks every url that is 56 * processed by the ServletResponse.encodeUrl method. 57 */ 58 public FacesContext getFacesContext(Object context, Object request, Object response, Lifecycle lifecycle) throws FacesException 59 { 60 if (response instanceof HttpServletResponse) 61 { 62 HttpServletRequest httpServletRequest = (HttpServletRequest) request; 63 64 // Wrap this request only if something else (eg a RequestParameterServletFilter) has not already wrapped it. 65 if (!Boolean.TRUE.equals(httpServletRequest.getAttribute(RequestParameterServletFilter.REQUEST_PARAM_FILTER_CALLED))) 66 { 67 // No servlet filter has wrapped the response, so do it now for the response referenced by this FacesContext. 68 // Note that this wrapper will therefore apply to all output generated via the FacesContext, but not to 69 // anything that might be written by filters etc. 70 response = new RequestParameterResponseWrapper((HttpServletResponse) response); 71 72 // We now need to reassure the RequestParameterProviderManager that the response has indeed been 73 // wrapped; it checks and reports an error if not as it is easy to stuff up this configuration. 74 // 75 // However we can not just set the REQUEST_PARAMETER_FILTER_CALLED flag here. If code creates its own 76 // FacesContext instance for any reason while a request is running, then this method is called again. 77 // On the second call this flag would already be set and the response would not be wrapped as required. 78 // 79 // Therefore we have two separate flags; RequestParameterProviderManager checks whether either 80 // REQUEST_PARAM_FILTER_CALLED or REQUEST_PARAM_RESPONSE_WRAPPED has been set. 81 82 httpServletRequest.setAttribute(RequestParameterServletFilter.REQUEST_PARAM_RESPONSE_WRAPPED, Boolean.TRUE); 83 84 } 85 } 86 87 return original.getFacesContext(context, request, response, lifecycle); 88 } 89 }