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1   package org.apache.velocity.runtime.parser.node;
2   
3   /*
4    * Licensed to the Apache Software Foundation (ASF) under one
5    * or more contributor license agreements.  See the NOTICE file
6    * distributed with this work for additional information
7    * regarding copyright ownership.  The ASF licenses this file
8    * to you under the Apache License, Version 2.0 (the
9    * "License"); you may not use this file except in compliance
10   * with the License.  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,
15   * software distributed under the License is distributed on an
16   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
17   * KIND, either express or implied.  See the License for the
18   * specific language governing permissions and limitations
19   * under the License.    
20   */
21  
22  import org.apache.velocity.context.InternalContextAdapter;
23  import org.apache.velocity.runtime.parser.Parser;
24  import org.apache.velocity.runtime.parser.ParserVisitor;
25  import org.apache.velocity.exception.MethodInvocationException;
26  
27  import org.apache.velocity.util.TemplateNumber;
28  
29  
30  /**
31   * Handles arg1 &gt;= arg2<br><br>
32   *
33   * Only subclasses of Number can be compared.<br><br>
34   *
35   * Please look at the Parser.jjt file which is
36   * what controls the generation of this class.
37   *
38   * @author <a href="mailto:wglass@forio.com">Will Glass-Husain</a>
39   * @author <a href="mailto:pero@antaramusic.de">Peter Romianowski</a>
40   */
41  public class ASTGENode extends SimpleNode
42  {
43      /**
44       * @param id
45       */
46      public ASTGENode(int id)
47      {
48          super(id);
49      }
50  
51      /**
52       * @param p
53       * @param id
54       */
55      public ASTGENode(Parser p, int id)
56      {
57          super(p, id);
58      }
59  
60  
61      /**
62       * @see org.apache.velocity.runtime.parser.node.SimpleNode#jjtAccept(org.apache.velocity.runtime.parser.ParserVisitor, java.lang.Object)
63       */
64      public Object jjtAccept(ParserVisitor visitor, Object data)
65      {
66          return visitor.visit(this, data);
67      }
68  
69      /**
70       * @see org.apache.velocity.runtime.parser.node.SimpleNode#evaluate(org.apache.velocity.context.InternalContextAdapter)
71       */
72      public boolean evaluate( InternalContextAdapter context)
73          throws MethodInvocationException
74      {
75          /*
76           *  get the two args
77           */
78  
79          Object left = jjtGetChild(0).value( context );
80          Object right = jjtGetChild(1).value( context );
81  
82          /*
83           *  if either is null, lets log and bail
84           */
85  
86          if (left == null || right == null)
87          {
88              log.error((left == null ? "Left" : "Right")
89                             + " side ("
90                             + jjtGetChild( (left == null? 0 : 1) ).literal()
91                             + ") of '>=' operation has null value."
92                             + " Operation not possible. "
93                             + context.getCurrentTemplateName() + " [line "
94                             + getLine()
95                             + ", column " + getColumn() + "]");
96              return false;
97          }
98  
99  
100         /*
101          *  convert to Number if applicable
102          */
103         if (left instanceof TemplateNumber)
104         {
105            left = ( (TemplateNumber) left).getAsNumber();
106         }
107         if (right instanceof TemplateNumber)
108         {
109            right = ( (TemplateNumber) right).getAsNumber();
110         }
111 
112         /*
113          *  Only compare Numbers
114          */
115 
116         if ( !( left instanceof Number )  || !( right instanceof Number ))
117         {
118             log.error((!(left instanceof Number) ? "Left" : "Right")
119                            + " side of '>=' operation is not a Number. "
120                            +  context.getCurrentTemplateName() + " [line " + getLine()
121                            + ", column " + getColumn() + "]");
122 
123             return false;
124         }
125 
126        return MathUtils.compare ( (Number)left,(Number)right) >= 0;
127 
128     }
129 
130     /**
131      * @see org.apache.velocity.runtime.parser.node.SimpleNode#value(org.apache.velocity.context.InternalContextAdapter)
132      */
133     public Object value(InternalContextAdapter context)
134         throws MethodInvocationException
135     {
136         boolean val = evaluate(context);
137 
138         return val ? Boolean.TRUE : Boolean.FALSE;
139     }
140 
141 }