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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   * LE : 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: ASTLENode.java 398203 2006-04-29 16:44:55Z dion $
29   */
30  public class ASTLENode extends SimpleNode {
31      /***
32       * Create the node given an id.
33       * 
34       * @param id node id.
35       */
36      public ASTLENode(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 ASTLENode(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) {
65              return Boolean.TRUE;
66          } else if ((left == null) || (right == null)) {
67              return Boolean.FALSE;
68          } else if (Coercion.isFloatingPoint(left)
69                  || Coercion.isFloatingPoint(right)) {
70              double leftDouble = Coercion.coerceDouble(left).doubleValue();
71              double rightDouble = Coercion.coerceDouble(right).doubleValue();
72  
73              return leftDouble <= rightDouble ? Boolean.TRUE : Boolean.FALSE;
74          } else if (Coercion.isNumberable(left) || Coercion.isNumberable(right)) {
75              long leftLong = Coercion.coerceLong(left).longValue();
76              long rightLong = Coercion.coerceLong(right).longValue();
77  
78              return leftLong <= rightLong ? Boolean.TRUE : Boolean.FALSE;
79          } else if (left instanceof String || right instanceof String) {
80              String leftString = left.toString();
81              String rightString = right.toString();
82  
83              return leftString.compareTo(rightString) <= 0 ? Boolean.TRUE
84                      : Boolean.FALSE;
85          } else if (left instanceof Comparable) {
86              return ((Comparable) left).compareTo(right) <= 0 ? Boolean.TRUE
87                      : Boolean.FALSE;
88          } else if (right instanceof Comparable) {
89              return ((Comparable) right).compareTo(left) >= 0 ? Boolean.TRUE
90                      : Boolean.FALSE;
91          }
92  
93          throw new Exception("Invalid comparison : LE ");
94      }
95  
96  }