1 | /* ============================================================= |
2 | * SmallSQL : a free Java DBMS library for the Java(tm) platform |
3 | * ============================================================= |
4 | * |
5 | * (C) Copyright 2004-2006, by Volker Berlin. |
6 | * |
7 | * Project Info: http://www.smallsql.de/ |
8 | * |
9 | * This library is free software; you can redistribute it and/or modify it |
10 | * under the terms of the GNU Lesser General Public License as published by |
11 | * the Free Software Foundation; either version 2.1 of the License, or |
12 | * (at your option) any later version. |
13 | * |
14 | * This library is distributed in the hope that it will be useful, but |
15 | * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY |
16 | * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public |
17 | * License for more details. |
18 | * |
19 | * You should have received a copy of the GNU Lesser General Public |
20 | * License along with this library; if not, write to the Free Software |
21 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, |
22 | * USA. |
23 | * |
24 | * [Java is a trademark or registered trademark of Sun Microsystems, Inc. |
25 | * in the United States and other countries.] |
26 | * |
27 | * --------------- |
28 | * ExpressionFunctionRound.java |
29 | * --------------- |
30 | * Author: Volker Berlin |
31 | * |
32 | */ |
33 | package smallsql.database; |
34 | |
35 | |
36 | final class ExpressionFunctionRound extends ExpressionFunctionReturnP1Number { |
37 | |
38 | final int getFunction(){ return SQLTokenizer.ROUND; } |
39 | |
40 | boolean isNull() throws Exception{ |
41 | return param1.isNull() || param2.isNull(); |
42 | } |
43 | |
44 | |
45 | final double getDouble() throws Exception{ |
46 | if(isNull()) return 0; |
47 | final int places = param2.getInt(); |
48 | double value = param1.getDouble(); |
49 | long factor = 1; |
50 | if(places > 0){ |
51 | for(int i=0; i<places; i++){ |
52 | factor *= 10; |
53 | } |
54 | value *= factor; |
55 | }else{ |
56 | for(int i=0; i>places; i--){ |
57 | factor *= 10; |
58 | } |
59 | value /= factor; |
60 | } |
61 | value = Math.rint( value ); |
62 | if(places > 0){ |
63 | value /= factor; |
64 | }else{ |
65 | value *= factor; |
66 | } |
67 | return value; |
68 | } |
69 | |
70 | |
71 | } |