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.jxpath.ri.compiler;
18
19 import org.apache.commons.jxpath.ri.QName;
20 import org.apache.commons.jxpath.ri.EvalContext;
21
22 /**
23 * An element of the compile tree holding a variable reference.
24 *
25 * @author Dmitri Plotnikov
26 * @version $Revision: 652845 $ $Date: 2008-05-02 19:46:46 +0200 (Fr, 02 Mai 2008) $
27 */
28 public class VariableReference extends Expression {
29
30 private QName varName;
31
32 /**
33 * Create a new VariableReference.
34 * @param varName variable name
35 */
36 public VariableReference(QName varName) {
37 this.varName = varName;
38 }
39
40 /**
41 * Get the variable name.
42 * @return QName
43 */
44 public QName getVariableName() {
45 return varName;
46 }
47
48 public String toString() {
49 return "$" + varName;
50 }
51
52 public boolean isContextDependent() {
53 return false;
54 }
55
56 public boolean computeContextDependent() {
57 return false;
58 }
59
60 public Object compute(EvalContext context) {
61 return computeValue(context);
62 }
63
64 /**
65 * Returns the value of the variable.
66 * @param context EvalContext against which to compute the variable's value.
67 * @return Object
68 */
69 public Object computeValue(EvalContext context) {
70 return context.getRootContext().getVariableContext(varName);
71 }
72 }