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1   /*
2    * reserved comment block
3    * DO NOT REMOVE OR ALTER!
4    */
5   /*
6    * Copyright 2001-2004 The Apache Software Foundation.
7    *
8    * Licensed under the Apache License, Version 2.0 (the "License");
9    * you may not use this file except in compliance with the License.
10   * You may obtain a copy of the License at
11   *
12   *     http://www.apache.org/licenses/LICENSE-2.0
13   *
14   * Unless required by applicable law or agreed to in writing, software
15   * distributed under the License is distributed on an "AS IS" BASIS,
16   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
17   * See the License for the specific language governing permissions and
18   * limitations under the License.
19   */
20  /*
21   * $Id: LocationPathPattern.java,v 1.2.4.1 2005/09/12 10:42:42 pvedula Exp $
22   */
23  
24  package com.sun.org.apache.xalan.internal.xsltc.compiler;
25  
26  import com.sun.org.apache.xalan.internal.xsltc.compiler.util.ClassGenerator;
27  import com.sun.org.apache.xalan.internal.xsltc.compiler.util.MethodGenerator;
28  import com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type;
29  import com.sun.org.apache.xalan.internal.xsltc.compiler.util.TypeCheckError;
30  import com.sun.org.apache.xml.internal.dtm.Axis;
31  
32  /**
33   * @author Jacek Ambroziak
34   * @author Santiago Pericas-Geertsen
35   * @author Morten Jorgensen
36   */
37  public abstract class LocationPathPattern extends Pattern {
38      private Template _template;
39      private int _importPrecedence;
40      private double _priority = Double.NaN;
41      private int _position = 0;
42  
43      public Type typeCheck(SymbolTable stable) throws TypeCheckError {
44          return Type.Void;               // TODO
45      }
46  
47      public void translate(ClassGenerator classGen, MethodGenerator methodGen) {
48          // TODO: What does it mean to translate a Pattern ?
49      }
50  
51      public void setTemplate(final Template template) {
52          _template = template;
53          _priority = template.getPriority();
54          _importPrecedence = template.getImportPrecedence();
55          _position = template.getPosition();
56      }
57  
58      public Template getTemplate() {
59          return _template;
60      }
61  
62      public final double getPriority() {
63          return Double.isNaN(_priority) ? getDefaultPriority() : _priority;
64      }
65  
66      public double getDefaultPriority() {
67          return 0.5;
68      }
69  
70      /**
71       * This method is used by the Mode class to prioritise patterns and
72       * template. This method is called for templates that are in the same
73       * mode and that match on the same core pattern. The rules used are:
74       *  o) first check precedence - highest precedence wins
75       *  o) then check priority - highest priority wins
76       *  o) then check the position - the template that occured last wins
77       */
78      public boolean noSmallerThan(LocationPathPattern other) {
79          if (_importPrecedence > other._importPrecedence) {
80              return true;
81          }
82          else if (_importPrecedence == other._importPrecedence) {
83              if (_priority > other._priority) {
84                  return true;
85              }
86              else if (_priority == other._priority) {
87                  if (_position > other._position) {
88                      return true;
89                  }
90              }
91          }
92          return false;
93      }
94  
95      public abstract StepPattern getKernelPattern();
96  
97      public abstract void reduceKernelPattern();
98  
99      public abstract boolean isWildcard();
100 
101     public int getAxis() {
102         final StepPattern sp = getKernelPattern();
103         return (sp != null) ? sp.getAxis() : Axis.CHILD;
104     }
105 
106     public String toString() {
107         return "root()";
108     }
109 }