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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: skitching $)
32   * @version $Revision: 684465 $ $Date: 2008-08-10 06:38:21 -0500 (Sun, 10 Aug 2008) $
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      public void release()
68      {
69          super.release();
70          _converterId = null;
71          _binding = null;
72          _converterIdString = null;
73      }
74  
75      protected Converter createConverter()
76              throws JspException
77      {
78          Converter converter = null;
79  
80          FacesContext facesContext = FacesContext.getCurrentInstance();
81          ELContext elContext = facesContext.getELContext();
82  
83          // try to create the converter from the binding expression first, and then from
84          // the converterId
85          if (_binding != null)
86          {
87              try
88              {
89                  converter = (Converter) _binding.getValue(elContext);
90  
91                  if (converter != null)
92                  {
93                      return converter;
94                  }
95              }
96              catch (Exception e)
97              {
98                  throw new JspException("Exception creating converter using binding", e);
99              }
100         }
101 
102         if ((_converterId != null) || (_converterIdString != null))
103         {
104             try
105             {
106                 if (null != _converterIdString)
107                 {
108                     converter = facesContext.getApplication().createConverter(_converterIdString);
109                 } else 
110                 {
111                     String converterId = (String) _converterId.getValue(elContext);
112                     converter = facesContext.getApplication().createConverter(converterId);
113                 }
114 
115                 // with binding no converter was created, set its value with the converter
116                 // created using the converterId
117                 if (converter != null && _binding != null)
118                 {
119                     _binding.setValue(elContext, converter);
120                 }
121             }
122             catch (Exception e)
123             {
124                 throw new JspException("Exception creating converter with converterId: " + _converterId, e);
125             }
126         }
127 
128         return converter;
129     }
130 
131 }