1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17 package org.apache.commons.el;
18
19 import javax.servlet.jsp.el.ELException;
20 import javax.servlet.jsp.el.FunctionMapper;
21 import javax.servlet.jsp.el.VariableResolver;
22
23 /**
24 *
25 * <p>Represents a name that can be used as the first element of a
26 * value.
27 *
28 * @author Nathan Abramson - Art Technology Group
29 * @author Shawn Bayern
30 * @version $Change: 181177 $$DateTime: 2001/06/26 08:45:09 $$Author: bayard $
31 **/
32
33 public class NamedValue
34 extends Expression
35 {
36 //-------------------------------------
37 // Constants
38 //-------------------------------------
39
40 //-------------------------------------
41 // Properties
42 //-------------------------------------
43 // property name
44
45 String mName;
46 public String getName ()
47 { return mName; }
48
49 //-------------------------------------
50 /**
51 *
52 * Constructor
53 **/
54 public NamedValue (String pName)
55 {
56 mName = pName;
57 }
58
59 //-------------------------------------
60 // Expression methods
61 //-------------------------------------
62 /**
63 *
64 * Returns the expression in the expression language syntax
65 **/
66 public String getExpressionString ()
67 {
68 return StringLiteral.toIdentifierToken (mName);
69 }
70
71 //-------------------------------------
72 /**
73 *
74 * Evaluates by looking up the name in the VariableResolver
75 **/
76 public Object evaluate (VariableResolver pResolver, FunctionMapper functions)
77 throws ELException
78 {
79 if (pResolver == null) {
80 return null;
81 }
82 else {
83 return pResolver.resolveVariable (mName);
84 }
85 }
86
87 public Expression bindFunctions(FunctionMapper functions) throws ELException {
88 return this;
89 }
90
91 //-------------------------------------
92 }