| 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 | * ExpressionFunctionSoundex.java |
| 29 | * --------------- |
| 30 | * Author: Volker Berlin |
| 31 | * |
| 32 | * Created on 18.06.2006 |
| 33 | */ |
| 34 | package smallsql.database; |
| 35 | |
| 36 | |
| 37 | /** |
| 38 | * @author Volker Berlin |
| 39 | */ |
| 40 | public class ExpressionFunctionSoundex extends ExpressionFunctionReturnP1StringAndBinary { |
| 41 | |
| 42 | final int getFunction() { |
| 43 | return SQLTokenizer.SOUNDEX; |
| 44 | } |
| 45 | |
| 46 | |
| 47 | final boolean isNull() throws Exception { |
| 48 | return param1.isNull(); |
| 49 | } |
| 50 | |
| 51 | |
| 52 | final byte[] getBytes() throws Exception{ |
| 53 | throw createUnspportedConversion(SQLTokenizer.BINARY); |
| 54 | } |
| 55 | |
| 56 | |
| 57 | final String getString() throws Exception { |
| 58 | if(isNull()) return null; |
| 59 | String input = param1.getString(); |
| 60 | return getString(input); |
| 61 | } |
| 62 | |
| 63 | |
| 64 | static String getString(String input){ |
| 65 | char[] output = new char[4]; |
| 66 | int idx = 0;; |
| 67 | input = input.toUpperCase(); |
| 68 | if(input.length()>0){ |
| 69 | output[idx++] = input.charAt(0); |
| 70 | } |
| 71 | char last = '0'; |
| 72 | for(int i=1; idx<4 && i<input.length(); i++){ |
| 73 | char c = input.charAt(i); |
| 74 | switch(c){ |
| 75 | case 'B': |
| 76 | case 'F': |
| 77 | case 'P': |
| 78 | case 'V': |
| 79 | c = '1'; |
| 80 | break; |
| 81 | case 'C': |
| 82 | case 'G': |
| 83 | case 'J': |
| 84 | case 'K': |
| 85 | case 'Q': |
| 86 | case 'S': |
| 87 | case 'X': |
| 88 | case 'Z': |
| 89 | c = '2'; |
| 90 | break; |
| 91 | case 'D': |
| 92 | case 'T': |
| 93 | c = '3'; |
| 94 | break; |
| 95 | case 'L': |
| 96 | c = '4'; |
| 97 | break; |
| 98 | case 'M': |
| 99 | case 'N': |
| 100 | c = '5'; |
| 101 | break; |
| 102 | case 'R': |
| 103 | c = '6'; |
| 104 | break; |
| 105 | default: |
| 106 | c = '0'; |
| 107 | break; |
| 108 | } |
| 109 | if(c > '0' && last != c){ |
| 110 | output[idx++] = c; |
| 111 | } |
| 112 | last = c; |
| 113 | } |
| 114 | for(; idx<4;){ |
| 115 | output[idx++] = '0'; |
| 116 | |
| 117 | } |
| 118 | return new String(output); |
| 119 | } |
| 120 | |
| 121 | |
| 122 | int getPrecision(){ |
| 123 | return 4; |
| 124 | } |
| 125 | } |