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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.exception.MethodInvocationException;
24  import org.apache.velocity.runtime.log.Log;
25  import org.apache.velocity.runtime.parser.Parser;
26  import org.apache.velocity.util.TemplateNumber;
27  
28  
29  /**
30   * Handles arg1 &gt;= arg2<br><br>
31   *
32   * Only subclasses of Number can be compared.<br><br>
33   *
34   * Please look at the Parser.jjt file which is
35   * what controls the generation of this class.
36   *
37   * @author <a href="mailto:wglass@forio.com">Will Glass-Husain</a>
38   * @author <a href="mailto:pero@antaramusic.de">Peter Romianowski</a>
39   */
40  public class ASTGENode extends SimpleNode
41  {
42      /**
43       * @param id
44       */
45      public ASTGENode(int id)
46      {
47          super(id);
48      }
49  
50      /**
51       * @param p
52       * @param id
53       */
54      public ASTGENode(Parser p, int id)
55      {
56          super(p, id);
57      }
58  
59  
60      /**
61       * @see org.apache.velocity.runtime.parser.node.SimpleNode#jjtAccept(org.apache.velocity.runtime.parser.node.ParserVisitor, java.lang.Object)
62       */
63      public Object jjtAccept(ParserVisitor visitor, Object data)
64      {
65          return visitor.visit(this, data);
66      }
67  
68      /**
69       * @see org.apache.velocity.runtime.parser.node.SimpleNode#evaluate(org.apache.velocity.context.InternalContextAdapter)
70       */
71      public boolean evaluate( InternalContextAdapter context)
72          throws MethodInvocationException
73      {
74          /*
75           *  get the two args
76           */
77  
78          Object left = jjtGetChild(0).value( context );
79          Object right = jjtGetChild(1).value( context );
80  
81          /*
82           *  if either is null, lets log and bail
83           */
84  
85          if (left == null || right == null)
86          {
87              log.error((left == null ? "Left" : "Right")
88                             + " side ("
89                             + jjtGetChild( (left == null? 0 : 1) ).literal()
90                             + ") of '>=' operation has null value."
91                             + " Operation not possible. "
92                             + Log.formatFileString(this));
93              return false;
94          }
95  
96  
97          /*
98           *  convert to Number if applicable
99           */
100         if (left instanceof TemplateNumber)
101         {
102            left = ( (TemplateNumber) left).getAsNumber();
103         }
104         if (right instanceof TemplateNumber)
105         {
106            right = ( (TemplateNumber) right).getAsNumber();
107         }
108 
109         /*
110          *  Only compare Numbers
111          */
112 
113         if ( !( left instanceof Number )  || !( right instanceof Number ))
114         {
115             log.error((!(left instanceof Number) ? "Left" : "Right")
116                            + " side of '>=' operation is not a Number. "
117                            + Log.formatFileString(this));
118 
119             return false;
120         }
121 
122        return MathUtils.compare ( (Number)left,(Number)right) >= 0;
123 
124     }
125 
126     /**
127      * @see org.apache.velocity.runtime.parser.node.SimpleNode#value(org.apache.velocity.context.InternalContextAdapter)
128      */
129     public Object value(InternalContextAdapter context)
130         throws MethodInvocationException
131     {
132         boolean val = evaluate(context);
133 
134         return val ? Boolean.TRUE : Boolean.FALSE;
135     }
136 
137 }