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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.Descriptors;
22  import com.google.protobuf.Message;
23  import com.google.protobuf.Service;
24  import com.google.protobuf.ServiceException;
25  
26  import org.apache.hadoop.hbase.classification.InterfaceAudience;
27  import org.apache.hadoop.hbase.classification.InterfaceStability;
28  import org.apache.hadoop.conf.Configuration;
29  import org.apache.hadoop.hbase.TableName;
30  import org.apache.hadoop.hbase.HTableDescriptor;
31  import org.apache.hadoop.hbase.KeyValue;
32  import org.apache.hadoop.hbase.client.coprocessor.Batch;
33  import org.apache.hadoop.hbase.filter.CompareFilter.CompareOp;
34  import org.apache.hadoop.hbase.ipc.CoprocessorRpcChannel;
35  
36  import java.io.Closeable;
37  import java.io.IOException;
38  import java.util.List;
39  import java.util.Map;
40  
41  /**
42   * Used to communicate with a single HBase table.
43   * Obtain an instance from an {@link HConnection}.
44   *
45   * @since 0.21.0
46   */
47  @InterfaceAudience.Public
48  @InterfaceStability.Stable
49  public interface HTableInterface extends Closeable {
50  
51    /**
52     * Gets the name of this table.
53     *
54     * @return the table name.
55     */
56    byte[] getTableName();
57  
58    /**
59     * Gets the fully qualified table name instance of this table.
60     */
61    TableName getName();
62  
63    /**
64     * Returns the {@link Configuration} object used by this instance.
65     * <p>
66     * The reference returned is not a copy, so any change made to it will
67     * affect this instance.
68     */
69    Configuration getConfiguration();
70  
71    /**
72     * Gets the {@link HTableDescriptor table descriptor} for this table.
73     * @throws IOException if a remote or network exception occurs.
74     */
75    HTableDescriptor getTableDescriptor() throws IOException;
76  
77    /**
78     * Test for the existence of columns in the table, as specified by the Get.
79     * <p>
80     *
81     * This will return true if the Get matches one or more keys, false if not.
82     * <p>
83     *
84     * This is a server-side call so it prevents any data from being transfered to
85     * the client.
86     *
87     * @param get the Get
88     * @return true if the specified Get matches one or more keys, false if not
89     * @throws IOException e
90     */
91    boolean exists(Get get) throws IOException;
92  
93    /**
94     * Test for the existence of columns in the table, as specified by the Gets.
95     * <p>
96     *
97     * This will return an array of booleans. Each value will be true if the related Get matches
98     * one or more keys, false if not.
99     * <p>
100    *
101    * This is a server-side call so it prevents any data from being transfered to
102    * the client.
103    *
104    * @param gets the Gets
105    * @return Array of Boolean true if the specified Get matches one or more keys, false if not
106    * @throws IOException e
107    */
108   Boolean[] exists(List<Get> gets) throws IOException;
109 
110   /**
111    * Method that does a batch call on Deletes, Gets, Puts, Increments, Appends and RowMutations.
112    * The ordering of execution of the actions is not defined. Meaning if you do a Put and a
113    * Get in the same {@link #batch} call, you will not necessarily be
114    * guaranteed that the Get returns what the Put had put.
115    *
116    * @param actions list of Get, Put, Delete, Increment, Append, RowMutations objects
117    * @param results Empty Object[], same size as actions. Provides access to partial
118    *                results, in case an exception is thrown. A null in the result array means that
119    *                the call for that action failed, even after retries
120    * @throws IOException
121    * @since 0.90.0
122    */
123   void batch(final List<?extends Row> actions, final Object[] results) throws IOException, InterruptedException;
124 
125   /**
126    * Same as {@link #batch(List, Object[])}, but returns an array of
127    * results instead of using a results parameter reference.
128    *
129    * @param actions list of Get, Put, Delete, Increment, Append, RowMutations objects
130    * @return the results from the actions. A null in the return array means that
131    *         the call for that action failed, even after retries
132    * @throws IOException
133    * @since 0.90.0
134    * @deprecated If any exception is thrown by one of the actions, there is no way to
135    * retrieve the partially executed results. Use {@link #batch(List, Object[])} instead.
136    */
137   Object[] batch(final List<? extends Row> actions) throws IOException, InterruptedException;
138 
139   /**
140    * Same as {@link #batch(List, Object[])}, but with a callback.
141    * @since 0.96.0
142    */
143   <R> void batchCallback(
144     final List<? extends Row> actions, final Object[] results, final Batch.Callback<R> callback
145   )
146     throws IOException, InterruptedException;
147 
148 
149   /**
150    * Same as {@link #batch(List)}, but with a callback.
151    * @since 0.96.0
152    * @deprecated If any exception is thrown by one of the actions, there is no way to
153    * retrieve the partially executed results. Use
154    * {@link #batchCallback(List, Object[], org.apache.hadoop.hbase.client.coprocessor.Batch.Callback)}
155    * instead.
156    */
157   <R> Object[] batchCallback(
158     List<? extends Row> actions, Batch.Callback<R> callback
159   ) throws IOException,
160     InterruptedException;
161 
162   /**
163    * Extracts certain cells from a given row.
164    * @param get The object that specifies what data to fetch and from which row.
165    * @return The data coming from the specified row, if it exists.  If the row
166    * specified doesn't exist, the {@link Result} instance returned won't
167    * contain any {@link KeyValue}, as indicated by {@link Result#isEmpty()}.
168    * @throws IOException if a remote or network exception occurs.
169    * @since 0.20.0
170    */
171   Result get(Get get) throws IOException;
172 
173   /**
174    * Extracts certain cells from the given rows, in batch.
175    *
176    * @param gets The objects that specify what data to fetch and from which rows.
177    *
178    * @return The data coming from the specified rows, if it exists.  If the row
179    *         specified doesn't exist, the {@link Result} instance returned won't
180    *         contain any {@link KeyValue}, as indicated by {@link Result#isEmpty()}.
181    *         If there are any failures even after retries, there will be a null in
182    *         the results array for those Gets, AND an exception will be thrown.
183    * @throws IOException if a remote or network exception occurs.
184    *
185    * @since 0.90.0
186    */
187   Result[] get(List<Get> gets) throws IOException;
188 
189   /**
190    * Return the row that matches <i>row</i> exactly,
191    * or the one that immediately precedes it.
192    *
193    * @param row A row key.
194    * @param family Column family to include in the {@link Result}.
195    * @throws IOException if a remote or network exception occurs.
196    * @since 0.20.0
197    * 
198    * @deprecated As of version 0.92 this method is deprecated without
199    * replacement.   
200    * getRowOrBefore is used internally to find entries in hbase:meta and makes
201    * various assumptions about the table (which are true for hbase:meta but not
202    * in general) to be efficient.
203    */
204   Result getRowOrBefore(byte[] row, byte[] family) throws IOException;
205 
206   /**
207    * Returns a scanner on the current table as specified by the {@link Scan}
208    * object.
209    * Note that the passed {@link Scan}'s start row and caching properties
210    * maybe changed.
211    *
212    * @param scan A configured {@link Scan} object.
213    * @return A scanner.
214    * @throws IOException if a remote or network exception occurs.
215    * @since 0.20.0
216    */
217   ResultScanner getScanner(Scan scan) throws IOException;
218 
219   /**
220    * Gets a scanner on the current table for the given family.
221    *
222    * @param family The column family 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) throws IOException;
228 
229   /**
230    * Gets a scanner on the current table for the given family and qualifier.
231    *
232    * @param family The column family to scan.
233    * @param qualifier The column qualifier to scan.
234    * @return A scanner.
235    * @throws IOException if a remote or network exception occurs.
236    * @since 0.20.0
237    */
238   ResultScanner getScanner(byte[] family, byte[] qualifier) throws IOException;
239 
240 
241   /**
242    * Puts some data in the table.
243    * <p>
244    * If {@link #isAutoFlush isAutoFlush} is false, the update is buffered
245    * until the internal buffer is full.
246    * @param put The data to put.
247    * @throws IOException if a remote or network exception occurs.
248    * @since 0.20.0
249    */
250   void put(Put put) throws IOException;
251 
252   /**
253    * Puts some data in the table, in batch.
254    * <p>
255    * If {@link #isAutoFlush isAutoFlush} is false, the update is buffered
256    * until the internal buffer is full.
257    * <p>
258    * This can be used for group commit, or for submitting user defined
259    * batches.  The writeBuffer will be periodically inspected while the List
260    * is processed, so depending on the List size the writeBuffer may flush
261    * not at all, or more than once.
262    * @param puts The list of mutations to apply. The batch put is done by
263    * aggregating the iteration of the Puts over the write buffer
264    * at the client-side for a single RPC call.
265    * @throws IOException if a remote or network exception occurs.
266    * @since 0.20.0
267    */
268   void put(List<Put> puts) throws IOException;
269 
270   /**
271    * Atomically checks if a row/family/qualifier value matches the expected
272    * value. If it does, it adds the put.  If the passed value is null, the check
273    * is for the lack of column (ie: non-existance)
274    *
275    * @param row to check
276    * @param family column family to check
277    * @param qualifier column qualifier to check
278    * @param value the expected value
279    * @param put data to put if check succeeds
280    * @throws IOException e
281    * @return true if the new put was executed, false otherwise
282    */
283   boolean checkAndPut(byte[] row, byte[] family, byte[] qualifier,
284       byte[] value, Put put) throws IOException;
285 
286   /**
287    * Deletes the specified cells/row.
288    *
289    * @param delete The object that specifies what to delete.
290    * @throws IOException if a remote or network exception occurs.
291    * @since 0.20.0
292    */
293   void delete(Delete delete) throws IOException;
294 
295   /**
296    * Deletes the specified cells/rows in bulk.
297    * @param deletes List of things to delete.  List gets modified by this
298    * method (in particular it gets re-ordered, so the order in which the elements
299    * are inserted in the list gives no guarantee as to the order in which the
300    * {@link Delete}s are executed).
301    * @throws IOException if a remote or network exception occurs. In that case
302    * the {@code deletes} argument will contain the {@link Delete} instances
303    * that have not be successfully applied.
304    * @since 0.20.1
305    */
306   void delete(List<Delete> deletes) throws IOException;
307 
308   /**
309    * Atomically checks if a row/family/qualifier value matches the expected
310    * value. If it does, it adds the delete.  If the passed value is null, the
311    * check is for the lack of column (ie: non-existance)
312    *
313    * @param row to check
314    * @param family column family to check
315    * @param qualifier column qualifier to check
316    * @param value the expected value
317    * @param delete data to delete if check succeeds
318    * @throws IOException e
319    * @return true if the new delete was executed, false otherwise
320    */
321   boolean checkAndDelete(byte[] row, byte[] family, byte[] qualifier,
322       byte[] value, Delete delete) throws IOException;
323 
324   /**
325    * Performs multiple mutations atomically on a single row. Currently
326    * {@link Put} and {@link Delete} are supported.
327    *
328    * @param rm object that specifies the set of mutations to perform atomically
329    * @throws IOException
330    */
331   void mutateRow(final RowMutations rm) throws IOException;
332 
333   /**
334    * Appends values to one or more columns within a single row.
335    * <p>
336    * This operation does not appear atomic to readers.  Appends are done
337    * under a single row lock, so write operations to a row are synchronized, but
338    * readers do not take row locks so get and scan operations can see this
339    * operation partially completed.
340    *
341    * @param append object that specifies the columns and amounts to be used
342    *                  for the increment operations
343    * @throws IOException e
344    * @return values of columns after the append operation (maybe null)
345    */
346   Result append(final Append append) throws IOException;
347 
348   /**
349    * Increments one or more columns within a single row.
350    * <p>
351    * This operation does not appear atomic to readers.  Increments are done
352    * under a single row lock, so write operations to a row are synchronized, but
353    * readers do not take row locks so get and scan operations can see this
354    * operation partially completed.
355    *
356    * @param increment object that specifies the columns and amounts to be used
357    *                  for the increment operations
358    * @throws IOException e
359    * @return values of columns after the increment
360    */
361   Result increment(final Increment increment) throws IOException;
362 
363   /**
364    * See {@link #incrementColumnValue(byte[], byte[], byte[], long, Durability)}
365    * <p>
366    * The {@link Durability} is defaulted to {@link Durability#SYNC_WAL}.
367    * @param row The row that contains the cell to increment.
368    * @param family The column family of the cell to increment.
369    * @param qualifier The column qualifier of the cell to increment.
370    * @param amount The amount to increment the cell with (or decrement, if the
371    * amount is negative).
372    * @return The new value, post increment.
373    * @throws IOException if a remote or network exception occurs.
374    */
375   long incrementColumnValue(byte[] row, byte[] family, byte[] qualifier,
376       long amount) throws IOException;
377 
378   /**
379    * Atomically increments a column value. If the column value already exists
380    * and is not a big-endian long, this could throw an exception. If the column
381    * value does not yet exist it is initialized to <code>amount</code> and
382    * written to the specified column.
383    *
384    * <p>Setting durability to {@link Durability#SKIP_WAL} means that in a fail
385    * scenario you will lose any increments that have not been flushed.
386    * @param row The row that contains the cell to increment.
387    * @param family The column family of the cell to increment.
388    * @param qualifier The column qualifier of the cell to increment.
389    * @param amount The amount to increment the cell with (or decrement, if the
390    * amount is negative).
391    * @param durability The persistence guarantee for this increment.
392    * @return The new value, post increment.
393    * @throws IOException if a remote or network exception occurs.
394    */
395   long incrementColumnValue(byte[] row, byte[] family, byte[] qualifier,
396       long amount, Durability durability) throws IOException;
397 
398   /**
399    * @deprecated Use {@link #incrementColumnValue(byte[], byte[], byte[], long, Durability)}
400    */
401   @Deprecated
402   long incrementColumnValue(final byte [] row, final byte [] family,
403       final byte [] qualifier, final long amount, final boolean writeToWAL)
404   throws IOException;
405 
406   /**
407    * Tells whether or not 'auto-flush' is turned on.
408    *
409    * @return {@code true} if 'auto-flush' is enabled (default), meaning
410    * {@link Put} operations don't get buffered/delayed and are immediately
411    * executed.
412    */
413   boolean isAutoFlush();
414 
415   /**
416    * Executes all the buffered {@link Put} operations.
417    * <p>
418    * This method gets called once automatically for every {@link Put} or batch
419    * of {@link Put}s (when <code>put(List<Put>)</code> is used) when
420    * {@link #isAutoFlush} is {@code true}.
421    * @throws IOException if a remote or network exception occurs.
422    */
423   void flushCommits() throws IOException;
424 
425   /**
426    * Releases any resources held or pending changes in internal buffers.
427    *
428    * @throws IOException if a remote or network exception occurs.
429    */
430   void close() throws IOException;
431 
432   /**
433    * Creates and returns a {@link com.google.protobuf.RpcChannel} instance connected to the
434    * table region containing the specified row.  The row given does not actually have
435    * to exist.  Whichever region would contain the row based on start and end keys will
436    * be used.  Note that the {@code row} parameter is also not passed to the
437    * coprocessor handler registered for this protocol, unless the {@code row}
438    * is separately passed as an argument in the service request.  The parameter
439    * here is only used to locate the region used to handle the call.
440    *
441    * <p>
442    * The obtained {@link com.google.protobuf.RpcChannel} instance can be used to access a published
443    * coprocessor {@link com.google.protobuf.Service} using standard protobuf service invocations:
444    * </p>
445    *
446    * <div style="background-color: #cccccc; padding: 2px">
447    * <blockquote><pre>
448    * CoprocessorRpcChannel channel = myTable.coprocessorService(rowkey);
449    * MyService.BlockingInterface service = MyService.newBlockingStub(channel);
450    * MyCallRequest request = MyCallRequest.newBuilder()
451    *     ...
452    *     .build();
453    * MyCallResponse response = service.myCall(null, request);
454    * </pre></blockquote></div>
455    *
456    * @param row The row key used to identify the remote region location
457    * @return A CoprocessorRpcChannel instance
458    */
459   CoprocessorRpcChannel coprocessorService(byte[] row);
460 
461   /**
462    * Creates an instance of the given {@link com.google.protobuf.Service} subclass for each table
463    * region spanning the range from the {@code startKey} row to {@code endKey} row (inclusive),
464    * and invokes the passed {@link org.apache.hadoop.hbase.client.coprocessor.Batch.Call#call}
465    * method with each {@link Service}
466    * instance.
467    *
468    * @param service the protocol buffer {@code Service} implementation to call
469    * @param startKey start region selection with region containing this row.  If {@code null}, the
470    *                 selection will start with the first table region.
471    * @param endKey select regions up to and including the region containing this row.
472    *               If {@code null}, selection will continue through the last table region.
473    * @param callable this instance's
474    *                 {@link org.apache.hadoop.hbase.client.coprocessor.Batch.Call#call}
475    *                 method will be invoked once per table region, using the {@link Service}
476    *                 instance connected to that region.
477    * @param <T> the {@link Service} subclass to connect to
478    * @param <R> Return type for the {@code callable} parameter's
479    * {@link org.apache.hadoop.hbase.client.coprocessor.Batch.Call#call} method
480    * @return a map of result values keyed by region name
481    */
482   <T extends Service, R> Map<byte[],R> coprocessorService(final Class<T> service,
483       byte[] startKey, byte[] endKey, final Batch.Call<T,R> callable)
484       throws ServiceException, Throwable;
485 
486   /**
487    * Creates an instance of the given {@link com.google.protobuf.Service} subclass for each table
488    * region spanning the range from the {@code startKey} row to {@code endKey} row (inclusive),
489    * and invokes the passed {@link org.apache.hadoop.hbase.client.coprocessor.Batch.Call#call}
490    * method with each {@link Service} instance.
491    *
492    * <p>
493    * The given
494    * {@link org.apache.hadoop.hbase.client.coprocessor.Batch.Callback#update(byte[], byte[], Object)}
495    * method will be called with the return value from each region's
496    * {@link org.apache.hadoop.hbase.client.coprocessor.Batch.Call#call} invocation.
497    *</p>
498    *
499    * @param service the protocol buffer {@code Service} implementation to call
500    * @param startKey start region selection with region containing this row.  If {@code null}, the
501    *                 selection will start with the first table region.
502    * @param endKey select regions up to and including the region containing this row.
503    *               If {@code null}, selection will continue through the last table region.
504    * @param callable this instance's
505    *                 {@link org.apache.hadoop.hbase.client.coprocessor.Batch.Call#call} method
506    *                 will be invoked once per table region, using the {@link Service} instance
507    *                 connected to that region.
508    * @param callback
509    * @param <T> the {@link Service} subclass to connect to
510    * @param <R> Return type for the {@code callable} parameter's
511    * {@link org.apache.hadoop.hbase.client.coprocessor.Batch.Call#call} method
512    */
513   <T extends Service, R> void coprocessorService(final Class<T> service,
514       byte[] startKey, byte[] endKey, final Batch.Call<T,R> callable,
515       final Batch.Callback<R> callback) throws ServiceException, Throwable;
516 
517   /**
518    * See {@link #setAutoFlush(boolean, boolean)}
519    *
520    * @param autoFlush
521    *          Whether or not to enable 'auto-flush'.
522    * @deprecated in 0.96. When called with setAutoFlush(false), this function also
523    *  set clearBufferOnFail to true, which is unexpected but kept for historical reasons.
524    *  Replace it with setAutoFlush(false, false) if this is exactly what you want, or by
525    *  {@link #setAutoFlushTo(boolean)} for all other cases.
526    */
527   @Deprecated
528   void setAutoFlush(boolean autoFlush);
529 
530   /**
531    * Turns 'auto-flush' on or off.
532    * <p>
533    * When enabled (default), {@link Put} operations don't get buffered/delayed
534    * and are immediately executed. Failed operations are not retried. This is
535    * slower but safer.
536    * <p>
537    * Turning off {@code #autoFlush} means that multiple {@link Put}s will be
538    * accepted before any RPC is actually sent to do the write operations. If the
539    * application dies before pending writes get flushed to HBase, data will be
540    * lost.
541    * <p>
542    * When you turn {@code #autoFlush} off, you should also consider the
543    * {@code #clearBufferOnFail} option. By default, asynchronous {@link Put}
544    * requests will be retried on failure until successful. However, this can
545    * pollute the writeBuffer and slow down batching performance. Additionally,
546    * you may want to issue a number of Put requests and call
547    * {@link #flushCommits()} as a barrier. In both use cases, consider setting
548    * clearBufferOnFail to true to erase the buffer after {@link #flushCommits()}
549    * has been called, regardless of success.
550    * <p>
551    * In other words, if you call {@code #setAutoFlush(false)}; HBase will retry N time for each
552    *  flushCommit, including the last one when closing the table. This is NOT recommended,
553    *  most of the time you want to call {@code #setAutoFlush(false, true)}.
554    *
555    * @param autoFlush
556    *          Whether or not to enable 'auto-flush'.
557    * @param clearBufferOnFail
558    *          Whether to keep Put failures in the writeBuffer. If autoFlush is true, then
559    *          the value of this parameter is ignored and clearBufferOnFail is set to true.
560    *          Setting clearBufferOnFail to false is deprecated since 0.96.
561    * @see #flushCommits
562    */
563   void setAutoFlush(boolean autoFlush, boolean clearBufferOnFail);
564 
565   /**
566    * Set the autoFlush behavior, without changing the value of {@code clearBufferOnFail}
567    */
568   void setAutoFlushTo(boolean autoFlush);
569 
570   /**
571    * Returns the maximum size in bytes of the write buffer for this HTable.
572    * <p>
573    * The default value comes from the configuration parameter
574    * {@code hbase.client.write.buffer}.
575    * @return The size of the write buffer in bytes.
576    */
577   long getWriteBufferSize();
578 
579   /**
580    * Sets the size of the buffer in bytes.
581    * <p>
582    * If the new size is less than the current amount of data in the
583    * write buffer, the buffer gets flushed.
584    * @param writeBufferSize The new write buffer size, in bytes.
585    * @throws IOException if a remote or network exception occurs.
586    */
587   void setWriteBufferSize(long writeBufferSize) throws IOException;
588 
589   /**
590    * Creates an instance of the given {@link com.google.protobuf.Service} subclass for each table
591    * region spanning the range from the {@code startKey} row to {@code endKey} row (inclusive), all
592    * the invocations to the same region server will be batched into one call. The coprocessor
593    * service is invoked according to the service instance, method name and parameters.
594    * 
595    * @param methodDescriptor
596    *          the descriptor for the protobuf service method to call.
597    * @param request
598    *          the method call parameters
599    * @param startKey
600    *          start region selection with region containing this row. If {@code null}, the
601    *          selection will start with the first table region.
602    * @param endKey
603    *          select regions up to and including the region containing this row. If {@code null},
604    *          selection will continue through the last table region.
605    * @param responsePrototype
606    *          the proto type of the response of the method in Service.
607    * @param <R>
608    *          the response type for the coprocessor Service method
609    * @throws ServiceException
610    * @throws Throwable
611    * @return a map of result values keyed by region name
612    */
613   <R extends Message> Map<byte[], R> batchCoprocessorService(
614       Descriptors.MethodDescriptor methodDescriptor, Message request,
615       byte[] startKey, byte[] endKey, R responsePrototype) throws ServiceException, Throwable;
616 
617   /**
618    * Creates an instance of the given {@link com.google.protobuf.Service} subclass for each table
619    * region spanning the range from the {@code startKey} row to {@code endKey} row (inclusive), all
620    * the invocations to the same region server will be batched into one call. The coprocessor
621    * service is invoked according to the service instance, method name and parameters.
622    * 
623    * <p>
624    * The given
625    * {@link org.apache.hadoop.hbase.client.coprocessor.Batch.Callback#update(byte[],byte[],Object)}
626    * method will be called with the return value from each region's invocation.
627    * </p>
628    * 
629    * @param methodDescriptor
630    *          the descriptor for the protobuf service method to call.
631    * @param request
632    *          the method call parameters
633    * @param startKey
634    *          start region selection with region containing this row. If {@code null}, the
635    *          selection will start with the first table region.
636    * @param endKey
637    *          select regions up to and including the region containing this row. If {@code null},
638    *          selection will continue through the last table region.
639    * @param responsePrototype
640    *          the proto type of the response of the method in Service.
641    * @param callback
642    *          callback to invoke with the response for each region
643    * @param <R>
644    *          the response type for the coprocessor Service method
645    * @throws ServiceException
646    * @throws Throwable
647    */
648   <R extends Message> void batchCoprocessorService(Descriptors.MethodDescriptor methodDescriptor,
649       Message request, byte[] startKey, byte[] endKey, R responsePrototype,
650       Batch.Callback<R> callback) throws ServiceException, Throwable;
651 
652   /**
653    * Atomically checks if a row/family/qualifier value matches the expected val
654    * If it does, it performs the row mutations.  If the passed value is null, t
655    * is for the lack of column (ie: non-existence)
656    *
657    * @param row to check
658    * @param family column family to check
659    * @param qualifier column qualifier to check
660    * @param compareOp the comparison operator
661    * @param value the expected value
662    * @param mutation  mutations to perform if check succeeds
663    * @throws IOException e
664    * @return true if the new put was executed, false otherwise
665    */
666   boolean checkAndMutate(byte[] row, byte[] family, byte[] qualifier, CompareOp compareOp,
667       byte[] value, RowMutations mutation) throws IOException;
668 }