| 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 | * ExpressionFunctionReplace.java |
| 29 | * --------------- |
| 30 | * Author: Volker Berlin |
| 31 | * |
| 32 | * Created on 23.06.2006 |
| 33 | */ |
| 34 | package smallsql.database; |
| 35 | |
| 36 | import java.io.ByteArrayOutputStream; |
| 37 | |
| 38 | |
| 39 | /** |
| 40 | * @author Volker Berlin |
| 41 | */ |
| 42 | public class ExpressionFunctionReplace extends ExpressionFunctionReturnP1StringAndBinary { |
| 43 | |
| 44 | final int getFunction() { |
| 45 | return SQLTokenizer.REPLACE; |
| 46 | } |
| 47 | |
| 48 | |
| 49 | final boolean isNull() throws Exception { |
| 50 | return param1.isNull() || param2.isNull() || param3.isNull(); |
| 51 | } |
| 52 | |
| 53 | |
| 54 | final byte[] getBytes() throws Exception{ |
| 55 | if(isNull()) return null; |
| 56 | byte[] str1 = param1.getBytes(); |
| 57 | byte[] str2 = param2.getBytes(); |
| 58 | int length = str2.length; |
| 59 | if(length == 0){ |
| 60 | return str1; |
| 61 | } |
| 62 | byte[] str3 = param3.getBytes(); |
| 63 | ByteArrayOutputStream buffer = new ByteArrayOutputStream(); |
| 64 | int idx1 = 0; |
| 65 | int idx2 = Utils.indexOf(str2,str1,idx1); |
| 66 | while(idx2 > 0){ |
| 67 | buffer.write(str1,idx1,idx2-idx1); |
| 68 | buffer.write(str3); |
| 69 | idx1 = idx2 + length; |
| 70 | idx2 = Utils.indexOf(str2,str1,idx1); |
| 71 | } |
| 72 | if(idx1 > 0){ |
| 73 | buffer.write(str1,idx1,str1.length-idx1); |
| 74 | return buffer.toByteArray(); |
| 75 | } |
| 76 | return str1; |
| 77 | } |
| 78 | |
| 79 | |
| 80 | final String getString() throws Exception { |
| 81 | if(isNull()) return null; |
| 82 | String str1 = param1.getString(); |
| 83 | String str2 = param2.getString(); |
| 84 | int length = str2.length(); |
| 85 | if(length == 0){ |
| 86 | return str1; |
| 87 | } |
| 88 | String str3 = param3.getString(); |
| 89 | StringBuffer buffer = new StringBuffer(); |
| 90 | int idx1 = 0; |
| 91 | int idx2 = str1.indexOf(str2,idx1); |
| 92 | while(idx2 >= 0){ |
| 93 | buffer.append(str1.substring(idx1,idx2)); |
| 94 | buffer.append(str3); |
| 95 | idx1 = idx2 + length; |
| 96 | idx2 = str1.indexOf(str2,idx1); |
| 97 | } |
| 98 | if(idx1 > 0){ |
| 99 | buffer.append(str1.substring(idx1)); |
| 100 | return buffer.toString(); |
| 101 | } |
| 102 | return str1; |
| 103 | } |
| 104 | |
| 105 | |
| 106 | int getPrecision() { |
| 107 | return SSResultSetMetaData.getDataTypePrecision( getDataType(), -1 ); |
| 108 | } |
| 109 | |
| 110 | } |