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1   /*
2    * Copyright 2002,2004 The Apache Software Foundation.
3    * 
4    * Licensed under the Apache License, Version 2.0 (the "License");
5    * you may not use this file except in compliance with the License.
6    * You may obtain a copy of the License at
7    * 
8    *      http://www.apache.org/licenses/LICENSE-2.0
9    * 
10   * Unless required by applicable law or agreed to in writing, software
11   * distributed under the License is distributed on an "AS IS" BASIS,
12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13   * See the License for the specific language governing permissions and
14   * limitations under the License.
15   */
16  
17  
18  package org.apache.commons.jexl.parser;
19  
20  import org.apache.commons.jexl.JexlContext;
21  
22  /***
23   *  Simple identifier -
24   *     $foo  or $foo.bar (both parts are identifiers...)
25   *
26   *  @author <a href="mailto:geirm@apache.org">Geir Magnusson Jr.</a>
27   *  @version $Id: ASTIdentifier.java,v 1.6 2004/02/28 13:45:20 yoavs Exp $
28   */
29  public class ASTIdentifier extends SimpleNode
30  {
31      protected String val;
32  
33      public ASTIdentifier(int id)
34      {
35          super(id);
36      }
37  
38      public ASTIdentifier(Parser p, int id)
39      {
40          super(p, id);
41      }
42  
43      /*** Accept the visitor. **/
44      public Object jjtAccept(ParserVisitor visitor, Object data)
45      {
46          return visitor.visit(this, data);
47      }
48  
49  
50      public Object value(JexlContext jc)
51          throws Exception
52      {
53          return jc.getVars().get(val);
54      }
55  
56      /***
57       *  returns the value of itself applied to the object.
58       *   We assume that an identifier can be gotten via a get(String)
59       */
60      public Object execute(Object obj, JexlContext jc)
61          throws Exception
62      {
63          return ASTArrayAccess.evaluateExpr(obj, val);
64      }
65  
66      public String getIdentifierString()
67      {
68          return val;
69      }
70  }