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1   /*
2    * Copyright 2002,2004 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.jexl.parser;
17  
18  import org.apache.commons.jexl.JexlContext;
19  import org.apache.commons.jexl.util.Coercion;
20  
21  /***
22   *  GT : a > b
23   *
24   *  Follows A.3.6.1 of the JSTL 1.0 specification
25   *
26   *  @author <a href="mailto:geirm@apache.org">Geir Magnusson Jr.</a>
27   *  @author <a href="mailto:proyal@apache.org">Peter Royal</a>
28   *  @version $Id: ASTGTNode.java,v 1.5 2004/02/28 13:45:20 yoavs Exp $
29   */
30  public class ASTGTNode extends SimpleNode
31  {
32      public ASTGTNode( int id )
33      {
34          super( id );
35      }
36  
37      public ASTGTNode( Parser p, int id )
38      {
39          super( p, id );
40      }
41  
42      /*** Accept the visitor. **/
43      public Object jjtAccept( ParserVisitor visitor, Object data )
44      {
45          return visitor.visit( this, data );
46      }
47  
48      public Object value( JexlContext jc )
49          throws Exception
50      {
51          /*
52           * now get the values
53           */
54  
55          Object left = ( (SimpleNode)jjtGetChild( 0 ) ).value( jc );
56          Object right = ( (SimpleNode)jjtGetChild( 1 ) ).value( jc );
57  
58          if( ( left == right ) || ( left == null ) || ( right == null ) )
59          {
60              return Boolean.FALSE;
61          }
62          else if( Coercion.isFloatingPoint( left ) || Coercion.isFloatingPoint( right ) )
63          {
64              double leftDouble = Coercion.coerceDouble( left ).doubleValue();
65              double rightDouble = Coercion.coerceDouble( right ).doubleValue();
66  
67              return leftDouble > rightDouble
68                  ? Boolean.TRUE
69                  : Boolean.FALSE;
70          }
71          else if( Coercion.isNumberable( left ) || Coercion.isNumberable( right ) )
72          {
73              long leftLong = Coercion.coerceLong( left ).longValue();
74              long rightLong = Coercion.coerceLong( right ).longValue();
75  
76              return leftLong > rightLong
77                  ? Boolean.TRUE
78                  : Boolean.FALSE;
79          }
80          else if( left instanceof String || right instanceof String )
81          {
82              String leftString = left.toString();
83              String rightString = right.toString();
84  
85              return leftString.compareTo( rightString ) > 0
86                  ? Boolean.TRUE
87                  : Boolean.FALSE;
88          }
89          else if( left instanceof Comparable )
90          {
91              return ( (Comparable)left ).compareTo( right ) > 0
92                  ? Boolean.TRUE
93                  : Boolean.FALSE;
94          }
95          else if( right instanceof Comparable )
96          {
97              return ( (Comparable)right ).compareTo( left ) < 0
98                  ? Boolean.TRUE
99                  : Boolean.FALSE;
100         }
101 
102         throw new Exception( "Invalid comparison : GT " );
103     }
104 }