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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   *  represents equality between integers - use .equals() for strings
23   *
24   *  @author <a href="mailto:geirm@apache.org">Geir Magnusson Jr.</a>
25   *  @version $Id: ASTEQNode.java,v 1.7 2004/08/22 01:53:27 dion Exp $
26   */
27  public class ASTEQNode extends SimpleNode
28  {
29      public ASTEQNode(int id)
30      {
31          super(id);
32      }
33  
34      public ASTEQNode(Parser p, int id)
35      {
36          super(p, id);
37      }
38  
39      /*** Accept the visitor. **/
40      public Object jjtAccept(ParserVisitor visitor, Object data)
41      {
42          return visitor.visit(this, data);
43      }
44  
45      public Object value(JexlContext pc)
46          throws Exception
47      {
48          Object left = ( (SimpleNode) jjtGetChild(0)).value(pc);
49          Object right = ( (SimpleNode) jjtGetChild(1)).value(pc);
50  
51          if (left == null && right == null)
52          {
53              /*
54               * if both are null L == R
55               */
56              return Boolean.TRUE;
57          }
58          else if (left==null || right==null)
59          {
60              /*
61               * we know both aren't null, therefore L != R
62               */
63              return Boolean.FALSE;
64          }
65          else if (left.getClass().equals(right.getClass()))
66          {
67              return left.equals(right) ? Boolean.TRUE : Boolean.FALSE;
68          }
69          else if(left instanceof Float || left instanceof Double ||
70                  right instanceof Float || right instanceof Double)
71          {
72              Double l = Coercion.coerceDouble(left);
73              Double r = Coercion.coerceDouble(right);
74  
75              return l.equals(r) ? Boolean.TRUE : Boolean.FALSE;
76          }
77          else if ( left instanceof Number || right instanceof Number ||
78                     left instanceof Character || right instanceof Character)
79          {
80              return Coercion.coerceLong(left).equals(Coercion.coerceLong(right)) 
81                  ? Boolean.TRUE : Boolean.FALSE;
82          }
83          else if (left instanceof Boolean || right instanceof Boolean)
84          {
85              return Coercion.coerceBoolean(left).equals(Coercion.coerceBoolean(right))
86                  ? Boolean.TRUE : Boolean.FALSE;
87          }
88          else if (left instanceof java.lang.String || right instanceof String)
89          {
90              return left.toString().equals(right.toString()) ? Boolean.TRUE : Boolean.FALSE;
91          }
92  
93          return left.equals(right) ? Boolean.TRUE : Boolean.FALSE;
94      }
95  }