View Javadoc

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.custom.security;
20  
21  import javax.faces.context.FacesContext;
22  import javax.faces.el.EvaluationException;
23  import javax.faces.el.VariableResolver;
24  
25  /**
26   * 
27   * @author cagatay
28   */
29  public class SecurityContextVariableResolver extends VariableResolver{
30  
31      private static final String SECURITY_CONTEXT = "securityContext";
32      private static final String INIT_PARAM_SECURITY_CONTEXT = "org.apache.myfaces.SECURITY_CONTEXT";
33  
34      private VariableResolver originalResolver;
35  
36      public SecurityContextVariableResolver(VariableResolver variableresolver) {
37          originalResolver = variableresolver;
38      }
39      
40      public Object resolveVariable(FacesContext facesContext, String name) throws EvaluationException {
41          if(SECURITY_CONTEXT.equals(name)) {
42              return getSecurityContextImpl(facesContext);
43          }
44          else {
45              return originalResolver.resolveVariable(facesContext, name);
46          }
47      }
48      
49      private Object getSecurityContextImpl(FacesContext facesContext) {
50          String className = (String) facesContext.getExternalContext().getInitParameter(INIT_PARAM_SECURITY_CONTEXT);
51          
52          if(className == null)
53              return new SecurityContextImpl();        //return default implementation
54          
55          try {
56              Class clazz = Class.forName(className);
57              return clazz.newInstance();
58          }catch(Exception e) {
59              throw new EvaluationException(e);
60          }
61      }
62  
63  }