1 /** 2 * 3 * Licensed to the Apache Software Foundation (ASF) under one 4 * or more contributor license agreements. See the NOTICE file 5 * distributed with this work for additional information 6 * regarding copyright ownership. The ASF licenses this file 7 * to you under the Apache License, Version 2.0 (the 8 * "License"); you may not use this file except in compliance 9 * with the License. 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 package org.apache.hadoop.hbase.client; 20 21 import com.google.protobuf.Service; 22 import com.google.protobuf.ServiceException; 23 import org.apache.hadoop.classification.InterfaceAudience; 24 import org.apache.hadoop.classification.InterfaceStability; 25 import org.apache.hadoop.conf.Configuration; 26 import org.apache.hadoop.hbase.TableName; 27 import org.apache.hadoop.hbase.HTableDescriptor; 28 import org.apache.hadoop.hbase.KeyValue; 29 import org.apache.hadoop.hbase.client.coprocessor.Batch; 30 import org.apache.hadoop.hbase.ipc.CoprocessorRpcChannel; 31 32 import java.io.Closeable; 33 import java.io.IOException; 34 import java.util.List; 35 import java.util.Map; 36 37 /** 38 * Used to communicate with a single HBase table. 39 * 40 * @since 0.21.0 41 */ 42 @InterfaceAudience.Public 43 @InterfaceStability.Stable 44 public interface HTableInterface extends Closeable { 45 46 /** 47 * Gets the name of this table. 48 * 49 * @return the table name. 50 */ 51 byte[] getTableName(); 52 53 /** 54 * Gets the fully qualified table name instance of this table. 55 */ 56 TableName getName(); 57 58 /** 59 * Returns the {@link Configuration} object used by this instance. 60 * <p> 61 * The reference returned is not a copy, so any change made to it will 62 * affect this instance. 63 */ 64 Configuration getConfiguration(); 65 66 /** 67 * Gets the {@link HTableDescriptor table descriptor} for this table. 68 * @throws IOException if a remote or network exception occurs. 69 */ 70 HTableDescriptor getTableDescriptor() throws IOException; 71 72 /** 73 * Test for the existence of columns in the table, as specified by the Get. 74 * <p> 75 * 76 * This will return true if the Get matches one or more keys, false if not. 77 * <p> 78 * 79 * This is a server-side call so it prevents any data from being transfered to 80 * the client. 81 * 82 * @param get the Get 83 * @return true if the specified Get matches one or more keys, false if not 84 * @throws IOException e 85 */ 86 boolean exists(Get get) throws IOException; 87 88 /** 89 * Test for the existence of columns in the table, as specified by the Gets. 90 * <p> 91 * 92 * This will return an array of booleans. Each value will be true if the related Get matches 93 * one or more keys, false if not. 94 * <p> 95 * 96 * This is a server-side call so it prevents any data from being transfered to 97 * the client. 98 * 99 * @param gets the Gets 100 * @return Array of Boolean true if the specified Get matches one or more keys, false if not 101 * @throws IOException e 102 */ 103 Boolean[] exists(List<Get> gets) throws IOException; 104 105 /** 106 * Method that does a batch call on Deletes, Gets, Puts, Increments, Appends and RowMutations. 107 * The ordering of execution of the actions is not defined. Meaning if you do a Put and a 108 * Get in the same {@link #batch} call, you will not necessarily be 109 * guaranteed that the Get returns what the Put had put. 110 * 111 * @param actions list of Get, Put, Delete, Increment, Append, RowMutations objects 112 * @param results Empty Object[], same size as actions. Provides access to partial 113 * results, in case an exception is thrown. A null in the result array means that 114 * the call for that action failed, even after retries 115 * @throws IOException 116 * @since 0.90.0 117 */ 118 void batch(final List<?extends Row> actions, final Object[] results) throws IOException, InterruptedException; 119 120 /** 121 * Same as {@link #batch(List, Object[])}, but returns an array of 122 * results instead of using a results parameter reference. 123 * 124 * @param actions list of Get, Put, Delete, Increment, Append, RowMutations objects 125 * @return the results from the actions. A null in the return array means that 126 * the call for that action failed, even after retries 127 * @throws IOException 128 * @since 0.90.0 129 */ 130 Object[] batch(final List<? extends Row> actions) throws IOException, InterruptedException; 131 132 /** 133 * Same as {@link #batch(List, Object[])}, but with a callback. 134 * @since 0.96.0 135 */ 136 <R> void batchCallback( 137 final List<? extends Row> actions, final Object[] results, final Batch.Callback<R> callback 138 ) 139 throws IOException, InterruptedException; 140 141 142 /** 143 * Same as {@link #batch(List)}, but with a callback. 144 * @since 0.96.0 145 */ 146 <R> Object[] batchCallback( 147 List<? extends Row> actions, Batch.Callback<R> callback 148 ) throws IOException, 149 InterruptedException; 150 151 /** 152 * Extracts certain cells from a given row. 153 * @param get The object that specifies what data to fetch and from which row. 154 * @return The data coming from the specified row, if it exists. If the row 155 * specified doesn't exist, the {@link Result} instance returned won't 156 * contain any {@link KeyValue}, as indicated by {@link Result#isEmpty()}. 157 * @throws IOException if a remote or network exception occurs. 158 * @since 0.20.0 159 */ 160 Result get(Get get) throws IOException; 161 162 /** 163 * Extracts certain cells from the given rows, in batch. 164 * 165 * @param gets The objects that specify what data to fetch and from which rows. 166 * 167 * @return The data coming from the specified rows, if it exists. If the row 168 * specified doesn't exist, the {@link Result} instance returned won't 169 * contain any {@link KeyValue}, as indicated by {@link Result#isEmpty()}. 170 * If there are any failures even after retries, there will be a null in 171 * the results array for those Gets, AND an exception will be thrown. 172 * @throws IOException if a remote or network exception occurs. 173 * 174 * @since 0.90.0 175 */ 176 Result[] get(List<Get> gets) throws IOException; 177 178 /** 179 * Return the row that matches <i>row</i> exactly, 180 * or the one that immediately precedes it. 181 * 182 * @param row A row key. 183 * @param family Column family to include in the {@link Result}. 184 * @throws IOException if a remote or network exception occurs. 185 * @since 0.20.0 186 * 187 * @deprecated As of version 0.92 this method is deprecated without 188 * replacement. 189 * getRowOrBefore is used internally to find entries in .META. and makes 190 * various assumptions about the table (which are true for .META. but not 191 * in general) to be efficient. 192 */ 193 Result getRowOrBefore(byte[] row, byte[] family) throws IOException; 194 195 /** 196 * Returns a scanner on the current table as specified by the {@link Scan} 197 * object. 198 * Note that the passed {@link Scan}'s start row and caching properties 199 * maybe changed. 200 * 201 * @param scan A configured {@link Scan} object. 202 * @return A scanner. 203 * @throws IOException if a remote or network exception occurs. 204 * @since 0.20.0 205 */ 206 ResultScanner getScanner(Scan scan) throws IOException; 207 208 /** 209 * Gets a scanner on the current table for the given family. 210 * 211 * @param family The column family to scan. 212 * @return A scanner. 213 * @throws IOException if a remote or network exception occurs. 214 * @since 0.20.0 215 */ 216 ResultScanner getScanner(byte[] family) throws IOException; 217 218 /** 219 * Gets a scanner on the current table for the given family and qualifier. 220 * 221 * @param family The column family to scan. 222 * @param qualifier The column qualifier to scan. 223 * @return A scanner. 224 * @throws IOException if a remote or network exception occurs. 225 * @since 0.20.0 226 */ 227 ResultScanner getScanner(byte[] family, byte[] qualifier) throws IOException; 228 229 230 /** 231 * Puts some data in the table. 232 * <p> 233 * If {@link #isAutoFlush isAutoFlush} is false, the update is buffered 234 * until the internal buffer is full. 235 * @param put The data to put. 236 * @throws IOException if a remote or network exception occurs. 237 * @since 0.20.0 238 */ 239 void put(Put put) throws IOException; 240 241 /** 242 * Puts some data in the table, in batch. 243 * <p> 244 * If {@link #isAutoFlush isAutoFlush} is false, the update is buffered 245 * until the internal buffer is full. 246 * <p> 247 * This can be used for group commit, or for submitting user defined 248 * batches. The writeBuffer will be periodically inspected while the List 249 * is processed, so depending on the List size the writeBuffer may flush 250 * not at all, or more than once. 251 * @param puts The list of mutations to apply. The batch put is done by 252 * aggregating the iteration of the Puts over the write buffer 253 * at the client-side for a single RPC call. 254 * @throws IOException if a remote or network exception occurs. 255 * @since 0.20.0 256 */ 257 void put(List<Put> puts) throws IOException; 258 259 /** 260 * Atomically checks if a row/family/qualifier value matches the expected 261 * value. If it does, it adds the put. If the passed value is null, the check 262 * is for the lack of column (ie: non-existance) 263 * 264 * @param row to check 265 * @param family column family to check 266 * @param qualifier column qualifier to check 267 * @param value the expected value 268 * @param put data to put if check succeeds 269 * @throws IOException e 270 * @return true if the new put was executed, false otherwise 271 */ 272 boolean checkAndPut(byte[] row, byte[] family, byte[] qualifier, 273 byte[] value, Put put) throws IOException; 274 275 /** 276 * Deletes the specified cells/row. 277 * 278 * @param delete The object that specifies what to delete. 279 * @throws IOException if a remote or network exception occurs. 280 * @since 0.20.0 281 */ 282 void delete(Delete delete) throws IOException; 283 284 /** 285 * Deletes the specified cells/rows in bulk. 286 * @param deletes List of things to delete. List gets modified by this 287 * method (in particular it gets re-ordered, so the order in which the elements 288 * are inserted in the list gives no guarantee as to the order in which the 289 * {@link Delete}s are executed). 290 * @throws IOException if a remote or network exception occurs. In that case 291 * the {@code deletes} argument will contain the {@link Delete} instances 292 * that have not be successfully applied. 293 * @since 0.20.1 294 */ 295 void delete(List<Delete> deletes) throws IOException; 296 297 /** 298 * Atomically checks if a row/family/qualifier value matches the expected 299 * value. If it does, it adds the delete. If the passed value is null, the 300 * check is for the lack of column (ie: non-existance) 301 * 302 * @param row to check 303 * @param family column family to check 304 * @param qualifier column qualifier to check 305 * @param value the expected value 306 * @param delete data to delete if check succeeds 307 * @throws IOException e 308 * @return true if the new delete was executed, false otherwise 309 */ 310 boolean checkAndDelete(byte[] row, byte[] family, byte[] qualifier, 311 byte[] value, Delete delete) throws IOException; 312 313 /** 314 * Performs multiple mutations atomically on a single row. Currently 315 * {@link Put} and {@link Delete} are supported. 316 * 317 * @param rm object that specifies the set of mutations to perform atomically 318 * @throws IOException 319 */ 320 void mutateRow(final RowMutations rm) throws IOException; 321 322 /** 323 * Appends values to one or more columns within a single row. 324 * <p> 325 * This operation does not appear atomic to readers. Appends are done 326 * under a single row lock, so write operations to a row are synchronized, but 327 * readers do not take row locks so get and scan operations can see this 328 * operation partially completed. 329 * 330 * @param append object that specifies the columns and amounts to be used 331 * for the increment operations 332 * @throws IOException e 333 * @return values of columns after the append operation (maybe null) 334 */ 335 Result append(final Append append) throws IOException; 336 337 /** 338 * Increments one or more columns within a single row. 339 * <p> 340 * This operation does not appear atomic to readers. Increments are done 341 * under a single row lock, so write operations to a row are synchronized, but 342 * readers do not take row locks so get and scan operations can see this 343 * operation partially completed. 344 * 345 * @param increment object that specifies the columns and amounts to be used 346 * for the increment operations 347 * @throws IOException e 348 * @return values of columns after the increment 349 */ 350 Result increment(final Increment increment) throws IOException; 351 352 /** 353 * See {@link #incrementColumnValue(byte[], byte[], byte[], long, Durability)} 354 * <p> 355 * The {@link Durability} is defaulted to {@link Durability#SYNC_WAL}. 356 * @param row The row that contains the cell to increment. 357 * @param family The column family of the cell to increment. 358 * @param qualifier The column qualifier of the cell to increment. 359 * @param amount The amount to increment the cell with (or decrement, if the 360 * amount is negative). 361 * @return The new value, post increment. 362 * @throws IOException if a remote or network exception occurs. 363 */ 364 long incrementColumnValue(byte[] row, byte[] family, byte[] qualifier, 365 long amount) throws IOException; 366 367 /** 368 * Atomically increments a column value. If the column value already exists 369 * and is not a big-endian long, this could throw an exception. If the column 370 * value does not yet exist it is initialized to <code>amount</code> and 371 * written to the specified column. 372 * 373 * <p>Setting durability to {@link Durability#SKIP_WAL} means that in a fail 374 * scenario you will lose any increments that have not been flushed. 375 * @param row The row that contains the cell to increment. 376 * @param family The column family of the cell to increment. 377 * @param qualifier The column qualifier of the cell to increment. 378 * @param amount The amount to increment the cell with (or decrement, if the 379 * amount is negative). 380 * @param durability The persistence guarantee for this increment. 381 * @return The new value, post increment. 382 * @throws IOException if a remote or network exception occurs. 383 */ 384 long incrementColumnValue(byte[] row, byte[] family, byte[] qualifier, 385 long amount, Durability durability) throws IOException; 386 387 /** 388 * Tells whether or not 'auto-flush' is turned on. 389 * 390 * @return {@code true} if 'auto-flush' is enabled (default), meaning 391 * {@link Put} operations don't get buffered/delayed and are immediately 392 * executed. 393 */ 394 boolean isAutoFlush(); 395 396 /** 397 * Executes all the buffered {@link Put} operations. 398 * <p> 399 * This method gets called once automatically for every {@link Put} or batch 400 * of {@link Put}s (when <code>put(List<Put>)</code> is used) when 401 * {@link #isAutoFlush} is {@code true}. 402 * @throws IOException if a remote or network exception occurs. 403 */ 404 void flushCommits() throws IOException; 405 406 /** 407 * Releases any resources held or pending changes in internal buffers. 408 * 409 * @throws IOException if a remote or network exception occurs. 410 */ 411 void close() throws IOException; 412 413 /** 414 * Creates and returns a {@link com.google.protobuf.RpcChannel} instance connected to the 415 * table region containing the specified row. The row given does not actually have 416 * to exist. Whichever region would contain the row based on start and end keys will 417 * be used. Note that the {@code row} parameter is also not passed to the 418 * coprocessor handler registered for this protocol, unless the {@code row} 419 * is separately passed as an argument in the service request. The parameter 420 * here is only used to locate the region used to handle the call. 421 * 422 * <p> 423 * The obtained {@link com.google.protobuf.RpcChannel} instance can be used to access a published 424 * coprocessor {@link com.google.protobuf.Service} using standard protobuf service invocations: 425 * </p> 426 * 427 * <div style="background-color: #cccccc; padding: 2px"> 428 * <blockquote><pre> 429 * CoprocessorRpcChannel channel = myTable.coprocessorService(rowkey); 430 * MyService.BlockingInterface service = MyService.newBlockingStub(channel); 431 * MyCallRequest request = MyCallRequest.newBuilder() 432 * ... 433 * .build(); 434 * MyCallResponse response = service.myCall(null, request); 435 * </pre></blockquote></div> 436 * 437 * @param row The row key used to identify the remote region location 438 * @return A CoprocessorRpcChannel instance 439 */ 440 CoprocessorRpcChannel coprocessorService(byte[] row); 441 442 /** 443 * Creates an instance of the given {@link com.google.protobuf.Service} subclass for each table 444 * region spanning the range from the {@code startKey} row to {@code endKey} row (inclusive), 445 * and invokes the passed {@link org.apache.hadoop.hbase.client.coprocessor.Batch.Call#call} 446 * method with each {@link Service} 447 * instance. 448 * 449 * @param service the protocol buffer {@code Service} implementation to call 450 * @param startKey start region selection with region containing this row. If {@code null}, the 451 * selection will start with the first table region. 452 * @param endKey select regions up to and including the region containing this row. 453 * If {@code null}, selection will continue through the last table region. 454 * @param callable this instance's 455 * {@link org.apache.hadoop.hbase.client.coprocessor.Batch.Call#call} 456 * method will be invoked once per table region, using the {@link Service} 457 * instance connected to that region. 458 * @param <T> the {@link Service} subclass to connect to 459 * @param <R> Return type for the {@code callable} parameter's 460 * {@link org.apache.hadoop.hbase.client.coprocessor.Batch.Call#call} method 461 * @return a map of result values keyed by region name 462 */ 463 <T extends Service, R> Map<byte[],R> coprocessorService(final Class<T> service, 464 byte[] startKey, byte[] endKey, final Batch.Call<T,R> callable) 465 throws ServiceException, Throwable; 466 467 /** 468 * Creates an instance of the given {@link com.google.protobuf.Service} subclass for each table 469 * region spanning the range from the {@code startKey} row to {@code endKey} row (inclusive), 470 * and invokes the passed {@link org.apache.hadoop.hbase.client.coprocessor.Batch.Call#call} 471 * method with each {@link Service} instance. 472 * 473 * <p> 474 * The given 475 * {@link org.apache.hadoop.hbase.client.coprocessor.Batch.Callback#update(byte[], byte[], Object)} 476 * method will be called with the return value from each region's 477 * {@link org.apache.hadoop.hbase.client.coprocessor.Batch.Call#call} invocation. 478 *</p> 479 * 480 * @param service the protocol buffer {@code Service} implementation to call 481 * @param startKey start region selection with region containing this row. If {@code null}, the 482 * selection will start with the first table region. 483 * @param endKey select regions up to and including the region containing this row. 484 * If {@code null}, selection will continue through the last table region. 485 * @param callable this instance's 486 * {@link org.apache.hadoop.hbase.client.coprocessor.Batch.Call#call} method 487 * will be invoked once per table region, using the {@link Service} instance 488 * connected to that region. 489 * @param callback 490 * @param <T> the {@link Service} subclass to connect to 491 * @param <R> Return type for the {@code callable} parameter's 492 * {@link org.apache.hadoop.hbase.client.coprocessor.Batch.Call#call} method 493 */ 494 <T extends Service, R> void coprocessorService(final Class<T> service, 495 byte[] startKey, byte[] endKey, final Batch.Call<T,R> callable, 496 final Batch.Callback<R> callback) throws ServiceException, Throwable; 497 498 /** 499 * See {@link #setAutoFlush(boolean, boolean)} 500 * 501 * @param autoFlush 502 * Whether or not to enable 'auto-flush'. 503 */ 504 void setAutoFlush(boolean autoFlush); 505 506 /** 507 * Turns 'auto-flush' on or off. 508 * <p> 509 * When enabled (default), {@link Put} operations don't get buffered/delayed 510 * and are immediately executed. Failed operations are not retried. This is 511 * slower but safer. 512 * <p> 513 * Turning off {@code autoFlush} means that multiple {@link Put}s will be 514 * accepted before any RPC is actually sent to do the write operations. If the 515 * application dies before pending writes get flushed to HBase, data will be 516 * lost. 517 * <p> 518 * When you turn {@code #autoFlush} off, you should also consider the 519 * {@code clearBufferOnFail} option. By default, asynchronous {@link Put} 520 * requests will be retried on failure until successful. However, this can 521 * pollute the writeBuffer and slow down batching performance. Additionally, 522 * you may want to issue a number of Put requests and call 523 * {@link #flushCommits()} as a barrier. In both use cases, consider setting 524 * clearBufferOnFail to true to erase the buffer after {@link #flushCommits()} 525 * has been called, regardless of success. 526 * 527 * @param autoFlush 528 * Whether or not to enable 'auto-flush'. 529 * @param clearBufferOnFail 530 * Whether to keep Put failures in the writeBuffer 531 * @see #flushCommits 532 */ 533 void setAutoFlush(boolean autoFlush, boolean clearBufferOnFail); 534 535 /** 536 * Returns the maximum size in bytes of the write buffer for this HTable. 537 * <p> 538 * The default value comes from the configuration parameter 539 * {@code hbase.client.write.buffer}. 540 * @return The size of the write buffer in bytes. 541 */ 542 long getWriteBufferSize(); 543 544 /** 545 * Sets the size of the buffer in bytes. 546 * <p> 547 * If the new size is less than the current amount of data in the 548 * write buffer, the buffer gets flushed. 549 * @param writeBufferSize The new write buffer size, in bytes. 550 * @throws IOException if a remote or network exception occurs. 551 */ 552 void setWriteBufferSize(long writeBufferSize) throws IOException; 553 }