| 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 | * UnionAll.java |
| 29 | * --------------- |
| 30 | * Author: Volker Berlin |
| 31 | * |
| 32 | * Created on 26.06.2004 |
| 33 | */ |
| 34 | package smallsql.database; |
| 35 | |
| 36 | |
| 37 | /** |
| 38 | * @author Volker Berlin |
| 39 | */ |
| 40 | final class UnionAll extends DataSource { |
| 41 | |
| 42 | private final DataSources dataSources = new DataSources(); |
| 43 | private int dataSourceIdx; |
| 44 | private DataSource currentDS; |
| 45 | private int row; |
| 46 | |
| 47 | |
| 48 | void addDataSource(DataSource ds){ |
| 49 | dataSources.add(ds); |
| 50 | currentDS = dataSources.get(0); |
| 51 | } |
| 52 | |
| 53 | |
| 54 | /*======================================================================= |
| 55 | |
| 56 | Methods for interface DataSource |
| 57 | |
| 58 | =======================================================================*/ |
| 59 | |
| 60 | boolean init(SSConnection con) throws Exception{ |
| 61 | boolean result = false; |
| 62 | int colCount = -1; |
| 63 | for(int i=0; i<dataSources.size(); i++){ |
| 64 | DataSource ds = dataSources.get(i); |
| 65 | result |= ds.init(con); |
| 66 | int nextColCount = ds.getTableView().columns.size(); |
| 67 | if(colCount == -1) |
| 68 | colCount = nextColCount; |
| 69 | else |
| 70 | if(colCount != nextColCount) |
| 71 | throw Utils.createSQLException("Different SELECT of the UNION have different column count:"+colCount+" and "+nextColCount); |
| 72 | } |
| 73 | return result; |
| 74 | } |
| 75 | |
| 76 | |
| 77 | final boolean isNull(int colIdx) throws Exception { |
| 78 | return currentDS.isNull(colIdx); |
| 79 | } |
| 80 | |
| 81 | |
| 82 | final boolean getBoolean(int colIdx) throws Exception { |
| 83 | return currentDS.getBoolean(colIdx); |
| 84 | } |
| 85 | |
| 86 | |
| 87 | final int getInt(int colIdx) throws Exception { |
| 88 | return currentDS.getInt(colIdx); |
| 89 | } |
| 90 | |
| 91 | |
| 92 | final long getLong(int colIdx) throws Exception { |
| 93 | return currentDS.getLong(colIdx); |
| 94 | } |
| 95 | |
| 96 | |
| 97 | final float getFloat(int colIdx) throws Exception { |
| 98 | return currentDS.getFloat(colIdx); |
| 99 | } |
| 100 | |
| 101 | |
| 102 | final double getDouble(int colIdx) throws Exception { |
| 103 | return currentDS.getDouble(colIdx); |
| 104 | } |
| 105 | |
| 106 | |
| 107 | final long getMoney(int colIdx) throws Exception { |
| 108 | return currentDS.getMoney(colIdx); |
| 109 | } |
| 110 | |
| 111 | |
| 112 | final MutableNumeric getNumeric(int colIdx) throws Exception { |
| 113 | return currentDS.getNumeric(colIdx); |
| 114 | } |
| 115 | |
| 116 | |
| 117 | final Object getObject(int colIdx) throws Exception { |
| 118 | return currentDS.getObject(colIdx); |
| 119 | } |
| 120 | |
| 121 | |
| 122 | final String getString(int colIdx) throws Exception { |
| 123 | return currentDS.getString(colIdx); |
| 124 | } |
| 125 | |
| 126 | |
| 127 | final byte[] getBytes(int colIdx) throws Exception { |
| 128 | return currentDS.getBytes(colIdx); |
| 129 | } |
| 130 | |
| 131 | |
| 132 | final int getDataType(int colIdx) { |
| 133 | return currentDS.getDataType(colIdx); |
| 134 | } |
| 135 | |
| 136 | |
| 137 | TableView getTableView(){ |
| 138 | return currentDS.getTableView(); |
| 139 | } |
| 140 | |
| 141 | |
| 142 | |
| 143 | /*======================================================================= |
| 144 | |
| 145 | Methods for interface RowSource |
| 146 | |
| 147 | =======================================================================*/ |
| 148 | |
| 149 | final boolean isScrollable(){ |
| 150 | return false; //TODO performance, can implement it if all datasources implement it |
| 151 | } |
| 152 | |
| 153 | |
| 154 | final void beforeFirst() throws Exception { |
| 155 | dataSourceIdx = 0; |
| 156 | currentDS = dataSources.get(0); |
| 157 | currentDS.beforeFirst(); |
| 158 | row = 0; |
| 159 | } |
| 160 | |
| 161 | |
| 162 | final boolean first() throws Exception { |
| 163 | dataSourceIdx = 0; |
| 164 | currentDS = dataSources.get(0); |
| 165 | boolean b = currentDS.first(); |
| 166 | row = b ? 1 : 0; |
| 167 | return b; |
| 168 | } |
| 169 | |
| 170 | |
| 171 | final boolean next() throws Exception { |
| 172 | boolean n = currentDS.next(); |
| 173 | row++; |
| 174 | if(n) return true; |
| 175 | while(dataSources.size() > dataSourceIdx+1){ |
| 176 | currentDS = dataSources.get(++dataSourceIdx); |
| 177 | currentDS.beforeFirst(); |
| 178 | n = currentDS.next(); |
| 179 | if(n) return true; |
| 180 | } |
| 181 | row = 0; |
| 182 | return false; |
| 183 | } |
| 184 | |
| 185 | |
| 186 | final void afterLast() throws Exception { |
| 187 | dataSourceIdx = dataSources.size()-1; |
| 188 | currentDS = dataSources.get(dataSourceIdx); |
| 189 | currentDS.afterLast(); |
| 190 | row = 0; |
| 191 | } |
| 192 | |
| 193 | |
| 194 | final int getRow() throws Exception { |
| 195 | return row; |
| 196 | } |
| 197 | |
| 198 | |
| 199 | private final int getBitCount(){ |
| 200 | int size = dataSources.size(); |
| 201 | int bitCount = 0; |
| 202 | while(size>0){ |
| 203 | bitCount++; |
| 204 | size >>= 1; |
| 205 | } |
| 206 | return bitCount; |
| 207 | } |
| 208 | |
| 209 | |
| 210 | final long getRowPosition() { |
| 211 | int bitCount = getBitCount(); |
| 212 | return dataSourceIdx | currentDS.getRowPosition() << bitCount; |
| 213 | } |
| 214 | |
| 215 | |
| 216 | final void setRowPosition(long rowPosition) throws Exception { |
| 217 | int bitCount = getBitCount(); |
| 218 | int mask = 0xFFFFFFFF >>> (32 - bitCount); |
| 219 | dataSourceIdx = (int)rowPosition & mask; |
| 220 | currentDS = dataSources.get(dataSourceIdx); |
| 221 | currentDS.setRowPosition( rowPosition >> bitCount ); |
| 222 | //getRow() is only unse on the top level RowSource, setRowPosition is not used on the top level RowSource |
| 223 | //thats we not set row here |
| 224 | } |
| 225 | |
| 226 | |
| 227 | final boolean rowInserted(){ |
| 228 | return currentDS.rowInserted(); |
| 229 | } |
| 230 | |
| 231 | |
| 232 | final boolean rowDeleted(){ |
| 233 | return currentDS.rowDeleted(); |
| 234 | } |
| 235 | |
| 236 | |
| 237 | final void nullRow() { |
| 238 | currentDS.nullRow(); |
| 239 | row = 0; |
| 240 | } |
| 241 | |
| 242 | |
| 243 | final void noRow() { |
| 244 | currentDS.noRow(); |
| 245 | row = 0; |
| 246 | } |
| 247 | |
| 248 | |
| 249 | final void execute() throws Exception{ |
| 250 | for(int i=0; i<dataSources.size(); i++){ |
| 251 | dataSources.get(i).execute(); |
| 252 | } |
| 253 | } |
| 254 | |
| 255 | } |