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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.EvalContext;
20  import org.apache.commons.jxpath.ri.axes.InitialContext;
21  
22  /**
23   * @author Dmitri Plotnikov
24   * @version $Revision: 652845 $ $Date: 2008-05-02 13:46:46 -0400 (Fri, 02 May 2008) $
25   */
26  public class LocationPath extends Path {
27  
28      private boolean absolute;
29  
30      /**
31       * Create a new LocationPath.
32       * @param absolute whether this is an absolute path
33       * @param steps to evaluate
34       */
35      public LocationPath(boolean absolute, Step[] steps) {
36          super(steps);
37          this.absolute = absolute;
38      }
39  
40      /**
41       * Learn whether this LocationPath is absolute.
42       * @return boolean
43       */
44      public boolean isAbsolute() {
45          return absolute;
46      }
47  
48      public boolean computeContextDependent() {
49          return !absolute || super.computeContextDependent();
50      }
51  
52      public String toString() {
53          StringBuffer buffer = new StringBuffer();
54          Step[] steps = getSteps();
55          if (steps != null) {
56              for (int i = 0; i < steps.length; i++) {
57                  if (i > 0 || absolute) {
58                      buffer.append('/');
59                  }
60                  buffer.append(steps[i]);
61              }
62          }
63          return buffer.toString();
64      }
65  
66      public Object compute(EvalContext context) {
67          // Create a chain of contexts
68          EvalContext rootContext;
69          if (isAbsolute()) {
70              rootContext = context.getRootContext().getAbsoluteRootContext();
71          }
72          else {
73              rootContext = new InitialContext(context);
74          }
75          return evalSteps(rootContext);
76      }
77  
78      public Object computeValue(EvalContext context) {
79          // Create a chain of contexts
80          EvalContext rootContext;
81          if (isAbsolute()) {
82              rootContext = context.getRootContext().getAbsoluteRootContext();
83          }
84          else {
85              rootContext = new InitialContext(context);
86          }
87          return getSingleNodePointerForSteps(rootContext);
88      }
89  }