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1   /*
2    * Copyright 2002-2006 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 398197 2006-04-29 16:18:04Z dion $
29   */
30  public class ASTGTNode extends SimpleNode {
31      /***
32       * Create the node given an id.
33       * 
34       * @param id node id.
35       */
36      public ASTGTNode(int id) {
37          super(id);
38      }
39  
40      /***
41       * Create a node with the given parser and id.
42       * 
43       * @param p a parser.
44       * @param id node id.
45       */
46      public ASTGTNode(Parser p, int id) {
47          super(p, id);
48      }
49  
50      /*** {@inheritDoc} */
51      public Object jjtAccept(ParserVisitor visitor, Object data) {
52          return visitor.visit(this, data);
53      }
54  
55      /*** {@inheritDoc} */
56      public Object value(JexlContext jc) throws Exception {
57          /*
58           * now get the values
59           */
60  
61          Object left = ((SimpleNode) jjtGetChild(0)).value(jc);
62          Object right = ((SimpleNode) jjtGetChild(1)).value(jc);
63  
64          if ((left == right) || (left == null) || (right == null)) {
65              return Boolean.FALSE;
66          } else if (Coercion.isFloatingPoint(left)
67                  || Coercion.isFloatingPoint(right)) {
68              double leftDouble = Coercion.coerceDouble(left).doubleValue();
69              double rightDouble = Coercion.coerceDouble(right).doubleValue();
70  
71              return leftDouble > rightDouble ? Boolean.TRUE : Boolean.FALSE;
72          } else if (Coercion.isNumberable(left) || Coercion.isNumberable(right)) {
73              long leftLong = Coercion.coerceLong(left).longValue();
74              long rightLong = Coercion.coerceLong(right).longValue();
75  
76              return leftLong > rightLong ? Boolean.TRUE : Boolean.FALSE;
77          } else if (left instanceof String || right instanceof String) {
78              String leftString = left.toString();
79              String rightString = right.toString();
80  
81              return leftString.compareTo(rightString) > 0 ? Boolean.TRUE
82                      : Boolean.FALSE;
83          } else if (left instanceof Comparable) {
84              return ((Comparable) left).compareTo(right) > 0 ? Boolean.TRUE
85                      : Boolean.FALSE;
86          } else if (right instanceof Comparable) {
87              return ((Comparable) right).compareTo(left) < 0 ? Boolean.TRUE
88                      : Boolean.FALSE;
89          }
90  
91          throw new Exception("Invalid comparison : GT ");
92      }
93  }