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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  
17  package org.apache.commons.jexl.parser;
18  
19  import org.apache.commons.jexl.JexlContext;
20  import org.apache.commons.jexl.util.Coercion;
21  
22  /***
23   *  Addition : either integer addition or string concatenation
24   *
25   *  @author <a href="mailto:geirm@apache.org">Geir Magnusson Jr.</a>
26   *  @version $Id: ASTAddNode.java,v 1.7 2004/08/24 02:22:12 dion Exp $
27   */
28  public class ASTAddNode extends SimpleNode
29  {
30      public ASTAddNode(int id)
31      {
32          super(id);
33      }
34  
35      public ASTAddNode(Parser p, int id)
36      {
37          super(p, id);
38      }
39  
40  
41      /*** Accept the visitor. **/
42      public Object jjtAccept(ParserVisitor visitor, Object data)
43      {
44          return visitor.visit(this, data);
45      }
46  
47      public Object value(JexlContext context)
48          throws Exception
49      {
50          Object left = ((SimpleNode) jjtGetChild(0)).value(context);
51          Object right = ((SimpleNode) jjtGetChild(1)).value(context);
52  
53          /*
54           *  the spec says 'and'
55           */
56          if (left == null && right == null)
57              return new Long(0);
58  
59          /*
60           *  if anything is float, double or string with ( "." | "E" | "e")
61           *  coerce all to doubles and do it
62           */
63          if (left instanceof Float || left instanceof Double
64              || right instanceof Float || right instanceof Double
65              || (  left instanceof String
66                    && (  ((String) left).indexOf(".") != -1 ||
67                          ((String) left).indexOf("e") != -1 ||
68                          ((String) left).indexOf("E") != -1 )
69                 )
70              || (  right instanceof String
71                    && (  ((String) right).indexOf(".") != -1 ||
72                          ((String) right).indexOf("e") != -1 ||
73                          ((String) right).indexOf("E") != -1)
74                 )
75              )
76          {
77  
78              /*
79               * in the event that either is null and not both, then just make the
80               * null a 0
81               */
82  
83              try
84              {
85                  Double l = left == null ? new Double(0) : Coercion.coerceDouble(left);
86                  Double r = right == null? new Double(0) : Coercion.coerceDouble(right);
87  
88                  return new Double(l.doubleValue() + r.doubleValue());
89              }
90              catch( java.lang.NumberFormatException nfe )
91              {
92                  /*
93                   * Well, use strings!
94                   */
95                  return left.toString().concat(right.toString());
96              }
97          }
98  
99          /*
100          * attempt to use Longs
101          */
102         try
103         {
104             Long l = left == null ? new Long(0) : Coercion.coerceLong(left);
105             Long r = right == null ? new Long(0) : Coercion.coerceLong(right);
106 
107             return new Long(l.longValue() + r.longValue());
108         }
109         catch( java.lang.NumberFormatException nfe )
110         {
111             /*
112              * Well, use strings!
113              */
114             return left.toString().concat(right.toString());
115         }
116     }
117 }