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Java > Open Source Codes > org > apache > cayenne > exp > parser > ASTNotEqual


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19
20
21 package org.apache.cayenne.exp.parser;
22
23 import org.apache.cayenne.exp.Expression;
24 import org.apache.cayenne.util.Util;
25
26 /**
27  * "Not equal to" expression.
28  *
29  * @author Andrus Adamchik
30  */
31 public class ASTNotEqual extends ConditionNode {
32     ASTNotEqual(int id) {
33         super(id);
34     }
35
36     public ASTNotEqual() {
37         super(ExpressionParserTreeConstants.JJTNOTEQUAL);
38     }
39
40     /**
41      * Creates "Not Equal To" expression.
42      */
43     public ASTNotEqual(ASTPath path, Object JavaDoc value) {
44         super(ExpressionParserTreeConstants.JJTNOTEQUAL);
45         jjtAddChild(path, 0);
46         jjtAddChild(new ASTScalar(value), 1);
47     }
48
49     protected Object JavaDoc evaluateNode(Object JavaDoc o) throws Exception JavaDoc {
50         int len = jjtGetNumChildren();
51         if (len != 2) {
52             return Boolean.FALSE;
53         }
54
55         Object JavaDoc o1 = evaluateChild(0, o);
56         Object JavaDoc o2 = evaluateChild(1, o);
57         return Util.nullSafeEquals(o1, o2) ? Boolean.FALSE : Boolean.TRUE;
58     }
59
60     /**
61      * Creates a copy of this expression node, without copying children.
62      */
63     public Expression shallowCopy() {
64         return new ASTNotEqual(id);
65     }
66
67     protected String JavaDoc getExpressionOperator(int index) {
68         return "!=";
69     }
70
71     public int getType() {
72         return Expression.NOT_EQUAL_TO;
73     }
74 }
75
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