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1   /*
2    * Copyright 1999-2004 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  package org.apache.commons.jxpath.ri.compiler;
17  
18  import org.apache.commons.jxpath.ri.Compiler;
19  
20  /***
21   * @author Dmitri Plotnikov
22   * @version $Revision: 1.9 $ $Date: 2004/02/29 14:17:39 $
23   */
24  public class Step {
25      private int axis;
26      private NodeTest nodeTest;
27      private Expression[] predicates;
28  
29      protected Step(int axis, NodeTest nodeTest, Expression[] predicates) {
30          this.axis = axis;
31          this.nodeTest = nodeTest;
32          this.predicates = predicates;
33      }
34  
35      public int getAxis() {
36          return axis;
37      }
38  
39      public NodeTest getNodeTest() {
40          return nodeTest;
41      }
42  
43      public Expression[] getPredicates() {
44          return predicates;
45      }
46  
47      public boolean isContextDependent() {
48          if (predicates != null) {
49              for (int i = 0; i < predicates.length; i++) {
50                  if (predicates[i].isContextDependent()) {
51                      return true;
52                  }
53              }
54          }
55          return false;
56      }
57  
58      public String toString() {
59          StringBuffer buffer = new StringBuffer();
60          int axis = getAxis();
61          if (axis == Compiler.AXIS_CHILD) {
62              buffer.append(nodeTest);
63          }
64          else if (axis == Compiler.AXIS_ATTRIBUTE) {
65              buffer.append('@');
66              buffer.append(nodeTest);
67          }
68          else if (axis == Compiler.AXIS_SELF
69                  && nodeTest instanceof NodeTypeTest
70                  && ((NodeTypeTest) nodeTest).getNodeType()
71                      == Compiler.NODE_TYPE_NODE) {
72              buffer.append(".");
73          }
74          else if (axis == Compiler.AXIS_PARENT
75                  && nodeTest instanceof NodeTypeTest
76                  && ((NodeTypeTest) nodeTest).getNodeType()
77                      == Compiler.NODE_TYPE_NODE) {
78              buffer.append("..");
79          }
80          else if (axis == Compiler.AXIS_DESCENDANT_OR_SELF
81                  && nodeTest instanceof NodeTypeTest
82                  && ((NodeTypeTest) nodeTest).getNodeType()
83                      == Compiler.NODE_TYPE_NODE 
84                  && (predicates == null || predicates.length == 0)) {
85              buffer.append("");
86          }
87          else {
88              buffer.append(axisToString(axis));
89              buffer.append("::");
90              buffer.append(nodeTest);
91          }
92          Expression[] predicates = getPredicates();
93          if (predicates != null) {
94              for (int i = 0; i < predicates.length; i++) {
95                  buffer.append('[');
96                  buffer.append(predicates[i]);
97                  buffer.append(']');
98              }
99          }
100         return buffer.toString();
101     }
102 
103     public static String axisToString(int axis) {
104         switch (axis) {
105             case Compiler.AXIS_SELF :
106                 return "self";
107             case Compiler.AXIS_CHILD :
108                 return "child";
109             case Compiler.AXIS_PARENT :
110                 return "parent";
111             case Compiler.AXIS_ANCESTOR :
112                 return "ancestor";
113             case Compiler.AXIS_ATTRIBUTE :
114                 return "attribute";
115             case Compiler.AXIS_NAMESPACE :
116                 return "namespace";
117             case Compiler.AXIS_PRECEDING :
118                 return "preceding";
119             case Compiler.AXIS_FOLLOWING :
120                 return "following";
121             case Compiler.AXIS_DESCENDANT :
122                 return "descendant";
123             case Compiler.AXIS_ANCESTOR_OR_SELF :
124                 return "ancestor-or-self";
125             case Compiler.AXIS_FOLLOWING_SIBLING :
126                 return "following-sibling";
127             case Compiler.AXIS_PRECEDING_SIBLING :
128                 return "preceding-sibling";
129             case Compiler.AXIS_DESCENDANT_OR_SELF :
130                 return "descendant-or-self";
131         }
132         return "UNKNOWN";
133     }
134 }