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 | |
20 | /** |
21 | * Handles integer modulus division |
22 | * |
23 | * Please look at the Parser.jjt file which is |
24 | * what controls the generation of this class. |
25 | * |
26 | * @author <a href="mailto:geirm@optonline.net">Geir Magnusson Jr.</a> |
27 | * @version $Id: ASTModNode.java,v 1.6.10.1 2004/03/03 23:22:59 geirm Exp $ |
28 | */ |
29 | import org.apache.velocity.context.InternalContextAdapter; |
30 | import org.apache.velocity.runtime.parser.Parser; |
31 | |
32 | import org.apache.velocity.exception.MethodInvocationException; |
33 | |
34 | public class ASTModNode extends SimpleNode |
35 | { |
36 | public ASTModNode(int id) |
37 | { |
38 | super(id); |
39 | } |
40 | |
41 | public ASTModNode(Parser p, int id) |
42 | { |
43 | super(p, id); |
44 | } |
45 | |
46 | /** Accept the visitor. **/ |
47 | public Object jjtAccept(ParserVisitor visitor, Object data) |
48 | { |
49 | return visitor.visit(this, data); |
50 | } |
51 | |
52 | public Object value( InternalContextAdapter context) |
53 | throws MethodInvocationException |
54 | { |
55 | /* |
56 | * get the two args |
57 | */ |
58 | |
59 | Object left = jjtGetChild(0).value( context ); |
60 | Object right = jjtGetChild(1).value( context ); |
61 | |
62 | /* |
63 | * if either is null, lets log and bail |
64 | */ |
65 | |
66 | if (left == null || right == null) |
67 | { |
68 | rsvc.error( ( left == null ? "Left" : "Right" ) + " side (" |
69 | + jjtGetChild( (left == null? 0 : 1) ).literal() |
70 | + ") of modulus operation has null value." |
71 | + " Operation not possible. " |
72 | + context.getCurrentTemplateName() + " [line " + getLine() |
73 | + ", column " + getColumn() + "]"); |
74 | return null; |
75 | } |
76 | |
77 | /* |
78 | * if not an Integer, not much we can do either |
79 | */ |
80 | |
81 | if ( !( left instanceof Integer ) || !( right instanceof Integer )) |
82 | { |
83 | rsvc.error( ( !( left instanceof Integer ) ? "Left" : "Right" ) |
84 | + " side of modulus operation is not a valid type. " |
85 | + "Currently only integers (1,2,3...) and Integer type is supported. " |
86 | + context.getCurrentTemplateName() + " [line " + getLine() |
87 | + ", column " + getColumn() + "]"); |
88 | |
89 | return null; |
90 | } |
91 | |
92 | /* |
93 | * check for divide by 0 |
94 | */ |
95 | |
96 | if ( ( (Integer) right).intValue() == 0 ) |
97 | { |
98 | rsvc.error( "Right side of modulus operation is zero. Must be non-zero. " |
99 | + context.getCurrentTemplateName() + " [line " + getLine() |
100 | + ", column " + getColumn() + "]"); |
101 | |
102 | return null; |
103 | } |
104 | |
105 | return new Integer( ( (Integer) left ).intValue() % ( (Integer) right ).intValue() ); |
106 | } |
107 | } |
108 | |