1 | package org.apache.velocity.runtime.parser.node; |
2 | |
3 | /* |
4 | * Copyright 2000-2001,2004 The Apache Software Foundation. |
5 | * |
6 | * Licensed under the Apache License, Version 2.0 (the "License"); |
7 | * you may not use this file except in compliance with the License. |
8 | * You may obtain a copy of the License at |
9 | * |
10 | * http://www.apache.org/licenses/LICENSE-2.0 |
11 | * |
12 | * Unless required by applicable law or agreed to in writing, software |
13 | * distributed under the License is distributed on an "AS IS" BASIS, |
14 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
15 | * See the License for the specific language governing permissions and |
16 | * limitations under the License. |
17 | */ |
18 | |
19 | import org.apache.velocity.context.InternalContextAdapter; |
20 | import org.apache.velocity.runtime.parser.Parser; |
21 | |
22 | import org.apache.velocity.exception.MethodInvocationException; |
23 | |
24 | public class ASTNENode extends SimpleNode |
25 | { |
26 | public ASTNENode(int id) |
27 | { |
28 | super(id); |
29 | } |
30 | |
31 | public ASTNENode(Parser p, int id) |
32 | { |
33 | super(p, id); |
34 | } |
35 | |
36 | /** Accept the visitor. **/ |
37 | public Object jjtAccept(ParserVisitor visitor, Object data) |
38 | { |
39 | return visitor.visit(this, data); |
40 | } |
41 | |
42 | public boolean evaluate( InternalContextAdapter context) |
43 | throws MethodInvocationException |
44 | { |
45 | Object left = jjtGetChild(0).value( context ); |
46 | Object right = jjtGetChild(1).value( context ); |
47 | |
48 | /* |
49 | * null check |
50 | */ |
51 | |
52 | if ( left == null || right == null) |
53 | { |
54 | rsvc.error( ( left == null ? "Left" : "Right" ) + " side (" |
55 | + jjtGetChild( (left == null? 0 : 1) ).literal() |
56 | + ") of '!=' operation has null value." |
57 | + " Operation not possible. " |
58 | + context.getCurrentTemplateName() + " [line " + getLine() |
59 | + ", column " + getColumn() + "]"); |
60 | return false; |
61 | |
62 | } |
63 | |
64 | |
65 | /* |
66 | * check to see if they are the same class. I don't think this is slower |
67 | * as I don't think that getClass() results in object creation, and we can |
68 | * extend == to handle all classes |
69 | */ |
70 | |
71 | if (left.getClass().equals( right.getClass() ) ) |
72 | { |
73 | return !(left.equals( right )); |
74 | } |
75 | else |
76 | { |
77 | rsvc.error("Error in evaluation of != expression." |
78 | + " Both arguments must be of the same Class." |
79 | + " Currently left = " + left.getClass() + ", right = " |
80 | + right.getClass() + ". " |
81 | + context.getCurrentTemplateName() + " [line " + getLine() |
82 | + ", column " + getColumn() + "] (ASTEQNode)"); |
83 | |
84 | return false; |
85 | } |
86 | } |
87 | |
88 | public Object value(InternalContextAdapter context) |
89 | throws MethodInvocationException |
90 | { |
91 | boolean val = evaluate(context); |
92 | |
93 | return val ? Boolean.TRUE : Boolean.FALSE; |
94 | } |
95 | |
96 | } |