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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.taglib.core;
20  
21  import javax.el.ELContext;
22  import javax.el.ValueExpression;
23  import javax.faces.context.FacesContext;
24  import javax.faces.convert.Converter;
25  import javax.faces.webapp.ConverterELTag;
26  import javax.servlet.jsp.JspException;
27  
28  /**
29   * Implementation of ConverterELTag
30   * 
31   * @author Bruno Aranda (latest modification by $Author: jakobk $)
32   * @version $Revision: 922543 $ $Date: 2010-03-13 06:55:01 -0500 (Sat, 13 Mar 2010) $
33   */
34  public class ConverterTag extends ConverterELTag
35  {
36  
37      private static final long serialVersionUID = -4506829108081L;
38      private ValueExpression _converterId;
39      private ValueExpression _binding;
40      private String _converterIdString = null;
41  
42      public ConverterTag()
43      {
44          super();
45      }
46  
47      public void setConverterId(ValueExpression converterId)
48      {
49          _converterId = converterId;
50      }
51  
52      public void setBinding(ValueExpression binding)
53      {
54          _binding = binding;
55      }
56  
57      /**
58       * Use this method to specify the converterId programmatically.
59       * 
60       * @param converterIdString
61       */
62      public void setConverterIdString(String converterIdString)
63      {
64          _converterIdString = converterIdString;
65      }
66  
67      @Override
68      public void release()
69      {
70          super.release();
71          _converterId = null;
72          _binding = null;
73          _converterIdString = null;
74      }
75  
76      @Override
77      protected Converter createConverter() throws JspException
78      {
79          Converter converter = null;
80  
81          FacesContext facesContext = FacesContext.getCurrentInstance();
82          ELContext elContext = facesContext.getELContext();
83  
84          // try to create the converter from the binding expression first, and then from
85          // the converterId
86          if (_binding != null)
87          {
88              try
89              {
90                  converter = (Converter)_binding.getValue(elContext);
91  
92                  if (converter != null)
93                  {
94                      return converter;
95                  }
96              }
97              catch (Exception e)
98              {
99                  throw new JspException("Exception creating converter using binding", e);
100             }
101         }
102 
103         if ((_converterId != null) || (_converterIdString != null))
104         {
105             try
106             {
107                 if (null != _converterIdString)
108                 {
109                     converter = facesContext.getApplication().createConverter(_converterIdString);
110                 }
111                 else
112                 {
113                     String converterId = (String)_converterId.getValue(elContext);
114                     converter = facesContext.getApplication().createConverter(converterId);
115                 }
116 
117                 // with binding no converter was created, set its value with the converter
118                 // created using the converterId
119                 if (converter != null && _binding != null)
120                 {
121                     _binding.setValue(elContext, converter);
122                 }
123             }
124             catch (Exception e)
125             {
126                 throw new JspException("Exception creating converter with converterId: " + _converterId, e);
127             }
128         }
129         
130         if (converter == null)
131         {
132             throw new JspException("Could not create converter. Please specify a valid converterId" +
133                     " or a non-null binding.");
134         }
135 
136         return converter;
137     }
138 
139 }