| 1 | /* |
| 2 | |
| 3 | Derby - Class org.apache.derby.iapi.sql.dictionary.IndexRowGenerator |
| 4 | |
| 5 | Copyright 1997, 2004 The Apache Software Foundation or its licensors, as applicable. |
| 6 | |
| 7 | Licensed under the Apache License, Version 2.0 (the "License"); |
| 8 | you may not use this file except in compliance with the License. |
| 9 | You may obtain a copy of the License at |
| 10 | |
| 11 | http://www.apache.org/licenses/LICENSE-2.0 |
| 12 | |
| 13 | Unless required by applicable law or agreed to in writing, software |
| 14 | distributed under the License is distributed on an "AS IS" BASIS, |
| 15 | WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 16 | See the License for the specific language governing permissions and |
| 17 | limitations under the License. |
| 18 | |
| 19 | */ |
| 20 | |
| 21 | package org.apache.derby.iapi.sql.dictionary; |
| 22 | |
| 23 | import org.apache.derby.iapi.sql.dictionary.ColumnDescriptorList; |
| 24 | import org.apache.derby.iapi.sql.conn.LanguageConnectionContext; |
| 25 | |
| 26 | import org.apache.derby.iapi.sql.execute.ExecutionContext; |
| 27 | import org.apache.derby.iapi.sql.execute.ExecIndexRow; |
| 28 | import org.apache.derby.iapi.sql.execute.ExecRow; |
| 29 | import org.apache.derby.iapi.sql.execute.ExecutionFactory; |
| 30 | |
| 31 | import org.apache.derby.iapi.types.RowLocation; |
| 32 | import org.apache.derby.iapi.types.DataTypeDescriptor; |
| 33 | |
| 34 | import org.apache.derby.iapi.services.io.Formatable; |
| 35 | import org.apache.derby.iapi.services.io.FormatIdUtil; |
| 36 | import org.apache.derby.iapi.services.io.StoredFormatIds; |
| 37 | |
| 38 | import org.apache.derby.iapi.services.sanity.SanityManager; |
| 39 | |
| 40 | import org.apache.derby.iapi.services.context.ContextService; |
| 41 | |
| 42 | import org.apache.derby.iapi.error.StandardException; |
| 43 | |
| 44 | import org.apache.derby.catalog.IndexDescriptor; |
| 45 | import org.apache.derby.catalog.types.IndexDescriptorImpl; |
| 46 | |
| 47 | import java.io.ObjectInput; |
| 48 | import java.io.ObjectOutput; |
| 49 | import java.io.IOException; |
| 50 | import org.apache.derby.iapi.services.io.FormatableBitSet; |
| 51 | |
| 52 | /** |
| 53 | * This class extends IndexDescriptor for internal use by the |
| 54 | * DataDictionary. |
| 55 | */ |
| 56 | public class IndexRowGenerator implements IndexDescriptor, Formatable |
| 57 | { |
| 58 | IndexDescriptor id; |
| 59 | private ExecutionFactory ef; |
| 60 | |
| 61 | /** |
| 62 | * Constructor for an IndexRowGeneratorImpl |
| 63 | * |
| 64 | * @param indexType The type of index |
| 65 | * @param isUnique True means the index is unique |
| 66 | * @param baseColumnPositions An array of column positions in the base |
| 67 | * table. Each index column corresponds to a |
| 68 | * column position in the base table. |
| 69 | * @param isAscending An array of booleans telling asc/desc on each |
| 70 | * column. |
| 71 | * @param numberOfOrderedColumns In the future, it will be possible |
| 72 | * to store non-ordered columns in an |
| 73 | * index. These will be useful for |
| 74 | * covered queries. |
| 75 | */ |
| 76 | public IndexRowGenerator(String indexType, |
| 77 | boolean isUnique, |
| 78 | int[] baseColumnPositions, |
| 79 | boolean[] isAscending, |
| 80 | int numberOfOrderedColumns) |
| 81 | { |
| 82 | id = new IndexDescriptorImpl(indexType, |
| 83 | isUnique, |
| 84 | baseColumnPositions, |
| 85 | isAscending, |
| 86 | numberOfOrderedColumns); |
| 87 | |
| 88 | if (SanityManager.DEBUG) |
| 89 | { |
| 90 | SanityManager.ASSERT(baseColumnPositions != null, |
| 91 | "baseColumnPositions are null"); |
| 92 | } |
| 93 | } |
| 94 | |
| 95 | /** |
| 96 | * Constructor for an IndexRowGeneratorImpl |
| 97 | * |
| 98 | * @param indexDescriptor An IndexDescriptor to delegate calls to |
| 99 | */ |
| 100 | public IndexRowGenerator(IndexDescriptor indexDescriptor) |
| 101 | { |
| 102 | id = indexDescriptor; |
| 103 | } |
| 104 | |
| 105 | /** |
| 106 | * Get a template for the index row, to be used with getIndexRow. |
| 107 | * |
| 108 | * @return A row template for the index row. |
| 109 | */ |
| 110 | public ExecIndexRow getIndexRowTemplate() |
| 111 | { |
| 112 | return getExecutionFactory().getIndexableRow( |
| 113 | id.baseColumnPositions().length + 1); |
| 114 | } |
| 115 | |
| 116 | /** |
| 117 | * Get an index row for this index given a row from the base table |
| 118 | * and the RowLocation of the base row. This method can be used |
| 119 | * to get the new index row for inserts, and the old and new index |
| 120 | * rows for deletes and updates. For updates, the result row has |
| 121 | * all the old column values followed by all of the new column values, |
| 122 | * so you must form a row using the new column values to pass to |
| 123 | * this method to get the new index row. |
| 124 | * |
| 125 | * @param baseRow A row in the base table |
| 126 | * @param rowLocation The RowLocation of the row in the base table |
| 127 | * @param indexRow A template for the index row. It must have the |
| 128 | * correct number of columns. |
| 129 | * @param bitSet If non-null, then baseRow is a partial row and the |
| 130 | * set bits in bitSet represents the column mapping for |
| 131 | * the partial row to the complete base row. <B> WARNING: |
| 132 | * </B> ONE based!!! |
| 133 | * |
| 134 | * @exception StandardException Thrown on error |
| 135 | */ |
| 136 | public void getIndexRow(ExecRow baseRow, |
| 137 | RowLocation rowLocation, |
| 138 | ExecIndexRow indexRow, |
| 139 | FormatableBitSet bitSet) |
| 140 | throws StandardException |
| 141 | { |
| 142 | /* |
| 143 | ** Set the columns in the index row that are based on columns in |
| 144 | ** the base row. |
| 145 | */ |
| 146 | int[] baseColumnPositions = id.baseColumnPositions(); |
| 147 | int colCount = baseColumnPositions.length; |
| 148 | |
| 149 | if (bitSet == null) |
| 150 | { |
| 151 | /* |
| 152 | ** Set the columns in the index row that are based on columns in |
| 153 | ** the base row. |
| 154 | */ |
| 155 | for (int i = 0; i < colCount ; i++) |
| 156 | { |
| 157 | indexRow.setColumn(i + 1, |
| 158 | baseRow.getColumn(baseColumnPositions[i])); |
| 159 | } |
| 160 | } |
| 161 | else |
| 162 | { |
| 163 | if (SanityManager.DEBUG) |
| 164 | { |
| 165 | SanityManager.ASSERT(!bitSet.get(0), "element zero of the bitSet passed into getIndexRow() is not false, bitSet should be 1 based"); |
| 166 | } |
| 167 | |
| 168 | /* |
| 169 | ** Set the columns in the index row that are based on columns in |
| 170 | ** the base row. |
| 171 | */ |
| 172 | for (int i = 0; i < colCount; i++) |
| 173 | { |
| 174 | int fullColumnNumber = baseColumnPositions[i]; |
| 175 | int partialColumnNumber = 0; |
| 176 | for (int index = 1; index <= fullColumnNumber; index++) |
| 177 | { |
| 178 | if (bitSet.get(index)) |
| 179 | { |
| 180 | partialColumnNumber++; |
| 181 | } |
| 182 | } |
| 183 | indexRow.setColumn(i + 1, |
| 184 | baseRow.getColumn(partialColumnNumber)); |
| 185 | } |
| 186 | } |
| 187 | |
| 188 | /* Set the row location in the last column of the index row */ |
| 189 | indexRow.setColumn(colCount + 1, rowLocation); |
| 190 | } |
| 191 | |
| 192 | /** |
| 193 | * Get a NULL Index Row for this index. This is useful to create objects |
| 194 | * that need to be passed to ScanController. |
| 195 | * |
| 196 | * @param columnList ColumnDescriptors describing the base table. |
| 197 | * @param rowLocation empty row location. |
| 198 | * |
| 199 | * @exception StandardException thrown on error. |
| 200 | */ |
| 201 | public ExecIndexRow getNullIndexRow(ColumnDescriptorList columnList, |
| 202 | RowLocation rowLocation) |
| 203 | throws StandardException |
| 204 | { |
| 205 | int[] baseColumnPositions = id.baseColumnPositions(); |
| 206 | int i; |
| 207 | ExecIndexRow indexRow = getIndexRowTemplate(); |
| 208 | |
| 209 | for (i = 0; i < baseColumnPositions.length; i++) |
| 210 | { |
| 211 | DataTypeDescriptor dtd = |
| 212 | columnList.elementAt(baseColumnPositions[i] - 1).getType(); |
| 213 | indexRow.setColumn(i + 1, dtd.getNull()); |
| 214 | } |
| 215 | |
| 216 | indexRow.setColumn(i + 1, rowLocation); |
| 217 | return indexRow; |
| 218 | } |
| 219 | |
| 220 | /** |
| 221 | * Return true iff a change to a set of columns changes the index for this |
| 222 | * IndexRowGenerator. |
| 223 | * |
| 224 | * @param changedColumnIds - holds the 1 based column ids for the changed |
| 225 | * columns. |
| 226 | * @return true iff a change to one of the columns in changedColumnIds |
| 227 | * effects this index. |
| 228 | */ |
| 229 | public boolean indexChanged(int[] changedColumnIds) |
| 230 | { |
| 231 | int[] baseColumnPositions = id.baseColumnPositions(); |
| 232 | |
| 233 | for (int ix = 0; ix < changedColumnIds.length; ix++) |
| 234 | { |
| 235 | for (int iy = 0; iy < baseColumnPositions.length; iy++) |
| 236 | { |
| 237 | if (changedColumnIds[ix] == baseColumnPositions[iy]) |
| 238 | return true; |
| 239 | } |
| 240 | } |
| 241 | return false; |
| 242 | } |
| 243 | |
| 244 | |
| 245 | /** |
| 246 | * Get the IndexDescriptor that this IndexRowGenerator is based on. |
| 247 | */ |
| 248 | public IndexDescriptor getIndexDescriptor() |
| 249 | { |
| 250 | return id; |
| 251 | } |
| 252 | |
| 253 | /** Zero-argument constructor for Formatable interface */ |
| 254 | public IndexRowGenerator() |
| 255 | { |
| 256 | } |
| 257 | |
| 258 | /** @see IndexDescriptor#isUnique */ |
| 259 | public boolean isUnique() |
| 260 | { |
| 261 | return id.isUnique(); |
| 262 | } |
| 263 | |
| 264 | /** @see IndexDescriptor#baseColumnPositions */ |
| 265 | public int[] baseColumnPositions() |
| 266 | { |
| 267 | return id.baseColumnPositions(); |
| 268 | } |
| 269 | |
| 270 | /** @see IndexDescriptor#getKeyColumnPosition */ |
| 271 | public Integer getKeyColumnPosition(Integer heapColumnPosition) |
| 272 | { |
| 273 | return id.getKeyColumnPosition(heapColumnPosition); |
| 274 | } |
| 275 | |
| 276 | /** @see IndexDescriptor#getKeyColumnPosition */ |
| 277 | public int getKeyColumnPosition(int heapColumnPosition) |
| 278 | { |
| 279 | return id.getKeyColumnPosition(heapColumnPosition); |
| 280 | } |
| 281 | |
| 282 | /** @see IndexDescriptor#numberOfOrderedColumns */ |
| 283 | public int numberOfOrderedColumns() |
| 284 | { |
| 285 | return id.numberOfOrderedColumns(); |
| 286 | } |
| 287 | |
| 288 | /** @see IndexDescriptor#indexType */ |
| 289 | public String indexType() |
| 290 | { |
| 291 | return id.indexType(); |
| 292 | } |
| 293 | |
| 294 | public String toString() |
| 295 | { |
| 296 | return id.toString(); |
| 297 | } |
| 298 | |
| 299 | /** @see IndexDescriptor#isAscending */ |
| 300 | public boolean isAscending(Integer keyColumnPosition) |
| 301 | { |
| 302 | return id.isAscending(keyColumnPosition); |
| 303 | } |
| 304 | |
| 305 | /** @see IndexDescriptor#isDescending */ |
| 306 | public boolean isDescending(Integer keyColumnPosition) |
| 307 | { |
| 308 | return id.isDescending(keyColumnPosition); |
| 309 | } |
| 310 | |
| 311 | /** @see IndexDescriptor#isAscending */ |
| 312 | public boolean[] isAscending() |
| 313 | { |
| 314 | return id.isAscending(); |
| 315 | } |
| 316 | |
| 317 | /** @see IndexDescriptor#setBaseColumnPositions */ |
| 318 | public void setBaseColumnPositions(int[] baseColumnPositions) |
| 319 | { |
| 320 | id.setBaseColumnPositions(baseColumnPositions); |
| 321 | } |
| 322 | |
| 323 | /** @see IndexDescriptor#setIsAscending */ |
| 324 | public void setIsAscending(boolean[] isAscending) |
| 325 | { |
| 326 | id.setIsAscending(isAscending); |
| 327 | } |
| 328 | |
| 329 | /** @see IndexDescriptor#setNumberOfOrderedColumns */ |
| 330 | public void setNumberOfOrderedColumns(int numberOfOrderedColumns) |
| 331 | { |
| 332 | id.setNumberOfOrderedColumns(numberOfOrderedColumns); |
| 333 | } |
| 334 | |
| 335 | /** |
| 336 | * Test for value equality |
| 337 | * |
| 338 | * @param other The other indexrowgenerator to compare this one with |
| 339 | * |
| 340 | * @return true if this indexrowgenerator has the same value as other |
| 341 | */ |
| 342 | |
| 343 | public boolean equals(Object other) |
| 344 | { |
| 345 | return id.equals(other); |
| 346 | } |
| 347 | |
| 348 | /** |
| 349 | @see java.lang.Object#hashCode |
| 350 | */ |
| 351 | public int hashCode() |
| 352 | { |
| 353 | return id.hashCode(); |
| 354 | } |
| 355 | |
| 356 | private ExecutionFactory getExecutionFactory() |
| 357 | { |
| 358 | if (ef == null) |
| 359 | { |
| 360 | ExecutionContext ec; |
| 361 | |
| 362 | ec = (ExecutionContext) |
| 363 | ContextService.getContext(ExecutionContext.CONTEXT_ID); |
| 364 | ef = ec.getExecutionFactory(); |
| 365 | } |
| 366 | return ef; |
| 367 | } |
| 368 | |
| 369 | //////////////////////////////////////////////////////////////////////////// |
| 370 | // |
| 371 | // EXTERNALIZABLE |
| 372 | // |
| 373 | //////////////////////////////////////////////////////////////////////////// |
| 374 | |
| 375 | /** |
| 376 | * @see java.io.Externalizable#readExternal |
| 377 | * |
| 378 | * @exception IOException Thrown on read error |
| 379 | * @exception ClassNotFoundException Thrown on read error |
| 380 | */ |
| 381 | public void readExternal(ObjectInput in) throws IOException, ClassNotFoundException |
| 382 | { |
| 383 | id = (IndexDescriptor)in.readObject(); |
| 384 | } |
| 385 | |
| 386 | /** |
| 387 | * |
| 388 | * @exception IOException Thrown on write error |
| 389 | */ |
| 390 | public void writeExternal(ObjectOutput out) throws IOException |
| 391 | { |
| 392 | out.writeObject(id); |
| 393 | } |
| 394 | |
| 395 | /* TypedFormat interface */ |
| 396 | public int getTypeFormatId() |
| 397 | { |
| 398 | return StoredFormatIds.INDEX_ROW_GENERATOR_V01_ID; |
| 399 | } |
| 400 | |
| 401 | } |