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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *      http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  package org.apache.commons.jexl.parser;
18  
19  import org.apache.commons.jexl.util.Coercion;
20  import org.apache.commons.jexl.JexlContext;
21  
22  /**
23   * a / b, mathematical divide.
24   * 
25   * @author <a href="mailto:geirm@apache.org">Geir Magnusson Jr.</a>
26   * @version $Id: ASTDivNode.java 480412 2006-11-29 05:11:23Z bayard $
27   */
28  public class ASTDivNode extends SimpleNode {
29      /**
30       * Create the node given an id.
31       * 
32       * @param id node id.
33       */
34      public ASTDivNode(int id) {
35          super(id);
36      }
37  
38      /**
39       * Create a node with the given parser and id.
40       * 
41       * @param p a parser.
42       * @param id node id.
43       */
44      public ASTDivNode(Parser p, int id) {
45          super(p, id);
46      }
47  
48      /** {@inheritDoc} */
49      public Object jjtAccept(ParserVisitor visitor, Object data) {
50          return visitor.visit(this, data);
51      }
52  
53      /** {@inheritDoc} */
54      public Object value(JexlContext jc) throws Exception {
55          Object left = ((SimpleNode) jjtGetChild(0)).value(jc);
56          Object right = ((SimpleNode) jjtGetChild(1)).value(jc);
57  
58          /*
59           * the spec says 'and', I think 'or'
60           */
61          if (left == null && right == null) {
62              return new Byte((byte) 0);
63          }
64  
65          Double l = Coercion.coerceDouble(left);
66          Double r = Coercion.coerceDouble(right);
67  
68          /*
69           * catch div/0
70           */
71          if (r.doubleValue() == 0.0) {
72              return new Double(0.0);
73          }
74  
75          return new Double(l.doubleValue() / r.doubleValue());
76  
77      }
78  }