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1   /**
2    * Licensed to the Apache Software Foundation (ASF) under one
3    * or more contributor license agreements.  See the NOTICE file
4    * distributed with this work for additional information
5    * regarding copyright ownership.  The ASF licenses this file
6    * to you under the Apache License, Version 2.0 (the
7    * "License"); you may not use this file except in compliance
8    * with the License.  You may obtain a copy of the License at
9    *
10   *     http://www.apache.org/licenses/LICENSE-2.0
11   *
12   * Unless required by applicable law or agreed to in writing, software
13   * distributed under the License is distributed on an "AS IS" BASIS,
14   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15   * See the License for the specific language governing permissions and
16   * limitations under the License.
17   */
18  package org.apache.hadoop.hbase;
19  
20  import static org.apache.hadoop.hbase.io.hfile.BlockType.MAGIC_LENGTH;
21  
22  import java.nio.ByteBuffer;
23  import java.nio.charset.Charset;
24  import java.util.Arrays;
25  import java.util.Collections;
26  import java.util.List;
27  import java.util.UUID;
28  import java.util.regex.Pattern;
29  
30  import org.apache.commons.lang.ArrayUtils;
31  import org.apache.hadoop.classification.InterfaceAudience;
32  import org.apache.hadoop.classification.InterfaceStability;
33  import org.apache.hadoop.hbase.util.Bytes;
34  
35  /**
36   * HConstants holds a bunch of HBase-related constants
37   */
38  @InterfaceAudience.Public
39  @InterfaceStability.Stable
40  public final class HConstants {
41    // NOTICE!!!! Please do not add a constants here, unless they are referenced by a lot of classes.
42  
43    //Bytes.UTF8_ENCODING should be updated if this changed
44    /** When we encode strings, we always specify UTF8 encoding */
45    public static final String UTF8_ENCODING = "UTF-8";
46  
47    //Bytes.UTF8_CHARSET should be updated if this changed
48    /** When we encode strings, we always specify UTF8 encoding */
49    public static final Charset UTF8_CHARSET = Charset.forName(UTF8_ENCODING);
50    /**
51     * Default block size for an HFile.
52     */
53    public final static int DEFAULT_BLOCKSIZE = 64 * 1024;
54  
55    /** Used as a magic return value while optimized index key feature enabled(HBASE-7845) */
56    public final static int INDEX_KEY_MAGIC = -2;
57    /*
58       * Name of directory that holds recovered edits written by the wal log
59       * splitting code, one per region
60       */
61    public static final String RECOVERED_EDITS_DIR = "recovered.edits";
62    /**
63     * The first four bytes of Hadoop RPC connections
64     */
65    public static final ByteBuffer RPC_HEADER = ByteBuffer.wrap("HBas".getBytes());
66    public static final byte RPC_CURRENT_VERSION = 0;
67  
68    // HFileBlock constants.
69  
70    /** The size data structures with minor version is 0 */
71    public static final int HFILEBLOCK_HEADER_SIZE_NO_CHECKSUM = MAGIC_LENGTH + 2 * Bytes.SIZEOF_INT
72        + Bytes.SIZEOF_LONG;
73    /** The size of a version 2 HFile block header, minor version 1.
74     * There is a 1 byte checksum type, followed by a 4 byte bytesPerChecksum
75     * followed by another 4 byte value to store sizeofDataOnDisk.
76     */
77    public static final int HFILEBLOCK_HEADER_SIZE = HFILEBLOCK_HEADER_SIZE_NO_CHECKSUM +
78      Bytes.SIZEOF_BYTE + 2 * Bytes.SIZEOF_INT;
79    /** Just an array of bytes of the right size. */
80    public static final byte[] HFILEBLOCK_DUMMY_HEADER = new byte[HFILEBLOCK_HEADER_SIZE];
81  
82    //End HFileBlockConstants.
83  
84    /**
85     * Status codes used for return values of bulk operations.
86     */
87    public enum OperationStatusCode {
88      NOT_RUN,
89      SUCCESS,
90      BAD_FAMILY,
91      SANITY_CHECK_FAILURE,
92      FAILURE;
93    }
94  
95    /** long constant for zero */
96    public static final Long ZERO_L = Long.valueOf(0L);
97    public static final String NINES = "99999999999999";
98    public static final String ZEROES = "00000000000000";
99  
100   // For migration
101 
102   /** name of version file */
103   public static final String VERSION_FILE_NAME = "hbase.version";
104 
105   /**
106    * Current version of file system.
107    * Version 4 supports only one kind of bloom filter.
108    * Version 5 changes versions in catalog table regions.
109    * Version 6 enables blockcaching on catalog tables.
110    * Version 7 introduces hfile -- hbase 0.19 to 0.20..
111    * Version 8 introduces namespace
112    */
113   // public static final String FILE_SYSTEM_VERSION = "6";
114   public static final String FILE_SYSTEM_VERSION = "8";
115 
116   // Configuration parameters
117 
118   //TODO: Is having HBase homed on port 60k OK?
119 
120   /** Cluster is in distributed mode or not */
121   public static final String CLUSTER_DISTRIBUTED = "hbase.cluster.distributed";
122 
123   /** Config for pluggable load balancers */
124   public static final String HBASE_MASTER_LOADBALANCER_CLASS = "hbase.master.loadbalancer.class";
125 
126   /** Cluster is standalone or pseudo-distributed */
127   public static final boolean CLUSTER_IS_LOCAL = false;
128 
129   /** Cluster is fully-distributed */
130   public static final boolean CLUSTER_IS_DISTRIBUTED = true;
131 
132   /** Default value for cluster distributed mode */
133   public static final boolean DEFAULT_CLUSTER_DISTRIBUTED = CLUSTER_IS_LOCAL;
134 
135   /** default host address */
136   public static final String DEFAULT_HOST = "0.0.0.0";
137 
138   /** Parameter name for port master listens on. */
139   public static final String MASTER_PORT = "hbase.master.port";
140 
141   /** default port that the master listens on */
142   public static final int DEFAULT_MASTER_PORT = 16000;
143 
144   /** default port for master web api */
145   public static final int DEFAULT_MASTER_INFOPORT = 16010;
146 
147   /** Configuration key for master web API port */
148   public static final String MASTER_INFO_PORT = "hbase.master.info.port";
149 
150   /** Parameter name for the master type being backup (waits for primary to go inactive). */
151   public static final String MASTER_TYPE_BACKUP = "hbase.master.backup";
152 
153   /** by default every master is a possible primary master unless the conf explicitly overrides it */
154   public static final boolean DEFAULT_MASTER_TYPE_BACKUP = false;
155 
156   /** Name of ZooKeeper quorum configuration parameter. */
157   public static final String ZOOKEEPER_QUORUM = "hbase.zookeeper.quorum";
158 
159   /** Name of ZooKeeper config file in conf/ directory. */
160   public static final String ZOOKEEPER_CONFIG_NAME = "zoo.cfg";
161 
162   /** Common prefix of ZooKeeper configuration properties */
163   public static final String ZK_CFG_PROPERTY_PREFIX =
164       "hbase.zookeeper.property.";
165 
166   public static final int ZK_CFG_PROPERTY_PREFIX_LEN =
167       ZK_CFG_PROPERTY_PREFIX.length();
168 
169   /**
170    * The ZK client port key in the ZK properties map. The name reflects the
171    * fact that this is not an HBase configuration key.
172    */
173   public static final String CLIENT_PORT_STR = "clientPort";
174 
175   /** Parameter name for the client port that the zookeeper listens on */
176   public static final String ZOOKEEPER_CLIENT_PORT =
177       ZK_CFG_PROPERTY_PREFIX + CLIENT_PORT_STR;
178 
179   /** Default client port that the zookeeper listens on */
180   public static final int DEFAULT_ZOOKEPER_CLIENT_PORT = 2181;
181 
182   /** Parameter name for the wait time for the recoverable zookeeper */
183   public static final String ZOOKEEPER_RECOVERABLE_WAITTIME = "hbase.zookeeper.recoverable.waittime";
184 
185   /** Default wait time for the recoverable zookeeper */
186   public static final long DEFAULT_ZOOKEPER_RECOVERABLE_WAITIME = 10000;
187 
188   /** Parameter name for the root dir in ZK for this cluster */
189   public static final String ZOOKEEPER_ZNODE_PARENT = "zookeeper.znode.parent";
190 
191   public static final String DEFAULT_ZOOKEEPER_ZNODE_PARENT = "/hbase";
192 
193   /**
194    * Parameter name for the limit on concurrent client-side zookeeper
195    * connections
196    */
197   public static final String ZOOKEEPER_MAX_CLIENT_CNXNS =
198       ZK_CFG_PROPERTY_PREFIX + "maxClientCnxns";
199 
200   /** Parameter name for the ZK data directory */
201   public static final String ZOOKEEPER_DATA_DIR =
202       ZK_CFG_PROPERTY_PREFIX + "dataDir";
203 
204   /** Default limit on concurrent client-side zookeeper connections */
205   public static final int DEFAULT_ZOOKEPER_MAX_CLIENT_CNXNS = 300;
206 
207   /** Configuration key for ZooKeeper session timeout */
208   public static final String ZK_SESSION_TIMEOUT = "zookeeper.session.timeout";
209 
210   /** Default value for ZooKeeper session timeout */
211   public static final int DEFAULT_ZK_SESSION_TIMEOUT = 180 * 1000;
212 
213   /** Configuration key for whether to use ZK.multi */
214   public static final String ZOOKEEPER_USEMULTI = "hbase.zookeeper.useMulti";
215 
216   /** Parameter name for port region server listens on. */
217   public static final String REGIONSERVER_PORT = "hbase.regionserver.port";
218 
219   /** Default port region server listens on. */
220   public static final int DEFAULT_REGIONSERVER_PORT = 16020;
221 
222   /** default port for region server web api */
223   public static final int DEFAULT_REGIONSERVER_INFOPORT = 16030;
224 
225   /** A configuration key for regionserver info port */
226   public static final String REGIONSERVER_INFO_PORT =
227     "hbase.regionserver.info.port";
228 
229   /** A flag that enables automatic selection of regionserver info port */
230   public static final String REGIONSERVER_INFO_PORT_AUTO =
231       REGIONSERVER_INFO_PORT + ".auto";
232 
233   /** Parameter name for what region server implementation to use. */
234   public static final String REGION_SERVER_IMPL= "hbase.regionserver.impl";
235 
236   /** Parameter name for what master implementation to use. */
237   public static final String MASTER_IMPL= "hbase.master.impl";
238 
239   /** Parameter name for what hbase client implementation to use. */
240   public static final String HBASECLIENT_IMPL= "hbase.hbaseclient.impl";
241 
242   /** Parameter name for how often threads should wake up */
243   public static final String THREAD_WAKE_FREQUENCY = "hbase.server.thread.wakefrequency";
244 
245   /** Default value for thread wake frequency */
246   public static final int DEFAULT_THREAD_WAKE_FREQUENCY = 10 * 1000;
247 
248   /** Parameter name for how often we should try to write a version file, before failing */
249   public static final String VERSION_FILE_WRITE_ATTEMPTS = "hbase.server.versionfile.writeattempts";
250 
251   /** Parameter name for how often we should try to write a version file, before failing */
252   public static final int DEFAULT_VERSION_FILE_WRITE_ATTEMPTS = 3;
253 
254   /** Parameter name for how often a region should should perform a major compaction */
255   public static final String MAJOR_COMPACTION_PERIOD = "hbase.hregion.majorcompaction";
256 
257   /** Parameter name for the maximum batch of KVs to be used in flushes and compactions */
258   public static final String COMPACTION_KV_MAX = "hbase.hstore.compaction.kv.max";
259   public static final int COMPACTION_KV_MAX_DEFAULT = 10;
260 
261   /** Parameter name for HBase instance root directory */
262   public static final String HBASE_DIR = "hbase.rootdir";
263 
264   /** Parameter name for HBase client IPC pool type */
265   public static final String HBASE_CLIENT_IPC_POOL_TYPE = "hbase.client.ipc.pool.type";
266 
267   /** Parameter name for HBase client IPC pool size */
268   public static final String HBASE_CLIENT_IPC_POOL_SIZE = "hbase.client.ipc.pool.size";
269 
270   /** Parameter name for HBase client operation timeout, which overrides RPC timeout */
271   public static final String HBASE_CLIENT_OPERATION_TIMEOUT = "hbase.client.operation.timeout";
272 
273   /** Parameter name for HBase client operation timeout, which overrides RPC timeout */
274   public static final String HBASE_CLIENT_META_OPERATION_TIMEOUT =
275     "hbase.client.meta.operation.timeout";
276 
277   /** Default HBase client operation timeout, which is tantamount to a blocking call */
278   public static final int DEFAULT_HBASE_CLIENT_OPERATION_TIMEOUT = Integer.MAX_VALUE;
279 
280   /** Used to construct the name of the log directory for a region server */
281   public static final String HREGION_LOGDIR_NAME = "WALs";
282 
283   /** Used to construct the name of the splitlog directory for a region server */
284   public static final String SPLIT_LOGDIR_NAME = "splitWAL";
285 
286   /** Like the previous, but for old logs that are about to be deleted */
287   public static final String HREGION_OLDLOGDIR_NAME = "oldWALs";
288 
289   public static final String CORRUPT_DIR_NAME = "corrupt";
290 
291   /** Used by HBCK to sideline backup data */
292   public static final String HBCK_SIDELINEDIR_NAME = ".hbck";
293 
294   /** Any artifacts left from migration can be moved here */
295   public static final String MIGRATION_NAME = ".migration";
296 
297   /**
298    * The directory from which co-processor/custom filter jars can be loaded
299    * dynamically by the region servers. This value can be overridden by the
300    * hbase.dynamic.jars.dir config.
301    */
302   public static final String LIB_DIR = "lib";
303 
304   /** Used to construct the name of the compaction directory during compaction */
305   public static final String HREGION_COMPACTIONDIR_NAME = "compaction.dir";
306 
307   /** Conf key for the max file size after which we split the region */
308   public static final String HREGION_MAX_FILESIZE =
309       "hbase.hregion.max.filesize";
310 
311   /** Default maximum file size */
312   public static final long DEFAULT_MAX_FILE_SIZE = 10 * 1024 * 1024 * 1024L;
313 
314   /**
315    * Max size of single row for Get's or Scan's without in-row scanning flag set.
316    */
317   public static final String TABLE_MAX_ROWSIZE_KEY = "hbase.table.max.rowsize";
318 
319   /**
320    * Default max row size (1 Gb).
321    */
322   public static final long TABLE_MAX_ROWSIZE_DEFAULT = 1024 * 1024 * 1024L;
323 
324   /**
325    * The max number of threads used for opening and closing stores or store
326    * files in parallel
327    */
328   public static final String HSTORE_OPEN_AND_CLOSE_THREADS_MAX =
329     "hbase.hstore.open.and.close.threads.max";
330 
331   /**
332    * The default number for the max number of threads used for opening and
333    * closing stores or store files in parallel
334    */
335   public static final int DEFAULT_HSTORE_OPEN_AND_CLOSE_THREADS_MAX = 1;
336 
337 
338   /** Conf key for the memstore size at which we flush the memstore */
339   public static final String HREGION_MEMSTORE_FLUSH_SIZE =
340       "hbase.hregion.memstore.flush.size";
341 
342   public static final String HREGION_EDITS_REPLAY_SKIP_ERRORS =
343       "hbase.hregion.edits.replay.skip.errors";
344 
345   public static final boolean DEFAULT_HREGION_EDITS_REPLAY_SKIP_ERRORS =
346       false;
347 
348   /** Maximum value length, enforced on KeyValue construction */
349   public static final int MAXIMUM_VALUE_LENGTH = Integer.MAX_VALUE - 1;
350 
351   /** name of the file for unique cluster ID */
352   public static final String CLUSTER_ID_FILE_NAME = "hbase.id";
353 
354   /** Default value for cluster ID */
355   public static final String CLUSTER_ID_DEFAULT = "default-cluster";
356 
357   // Always store the location of the root table's HRegion.
358   // This HRegion is never split.
359 
360   // region name = table + startkey + regionid. This is the row key.
361   // each row in the root and meta tables describes exactly 1 region
362   // Do we ever need to know all the information that we are storing?
363 
364   // Note that the name of the root table starts with "-" and the name of the
365   // meta table starts with "." Why? it's a trick. It turns out that when we
366   // store region names in memory, we use a SortedMap. Since "-" sorts before
367   // "." (and since no other table name can start with either of these
368   // characters, the root region will always be the first entry in such a Map,
369   // followed by all the meta regions (which will be ordered by their starting
370   // row key as well), followed by all user tables. So when the Master is
371   // choosing regions to assign, it will always choose the root region first,
372   // followed by the meta regions, followed by user regions. Since the root
373   // and meta regions always need to be on-line, this ensures that they will
374   // be the first to be reassigned if the server(s) they are being served by
375   // should go down.
376 
377 
378   /** The hbase:meta table's name. */
379   @Deprecated  // for compat from 0.94 -> 0.96.
380   public static final byte[] META_TABLE_NAME = TableName.META_TABLE_NAME.getName();
381 
382   public static final String BASE_NAMESPACE_DIR = "data";
383 
384   /** delimiter used between portions of a region name */
385   public static final int META_ROW_DELIMITER = ',';
386 
387   /** The catalog family as a string*/
388   public static final String CATALOG_FAMILY_STR = "info";
389 
390   /** The catalog family */
391   public static final byte [] CATALOG_FAMILY = Bytes.toBytes(CATALOG_FAMILY_STR);
392 
393   /** The RegionInfo qualifier as a string */
394   public static final String REGIONINFO_QUALIFIER_STR = "regioninfo";
395 
396   /** The regioninfo column qualifier */
397   public static final byte [] REGIONINFO_QUALIFIER = Bytes.toBytes(REGIONINFO_QUALIFIER_STR);
398 
399   /** The server column qualifier */
400   public static final byte [] SERVER_QUALIFIER = Bytes.toBytes("server");
401 
402   /** The startcode column qualifier */
403   public static final byte [] STARTCODE_QUALIFIER = Bytes.toBytes("serverstartcode");
404 
405   /** The open seqnum column qualifier */
406   public static final byte [] SEQNUM_QUALIFIER = Bytes.toBytes("seqnumDuringOpen");
407 
408   /** The state column qualifier */
409   public static final byte [] STATE_QUALIFIER = Bytes.toBytes("state");
410 
411   /**
412    * The serverName column qualifier. Its the server where the region is
413    * transitioning on, while column server is the server where the region is
414    * opened on. They are the same when the region is in state OPEN.
415    */
416   public static final byte [] SERVERNAME_QUALIFIER = Bytes.toBytes("sn");
417 
418   /** The lower-half split region column qualifier */
419   public static final byte [] SPLITA_QUALIFIER = Bytes.toBytes("splitA");
420 
421   /** The upper-half split region column qualifier */
422   public static final byte [] SPLITB_QUALIFIER = Bytes.toBytes("splitB");
423 
424   /** The lower-half merge region column qualifier */
425   public static final byte[] MERGEA_QUALIFIER = Bytes.toBytes("mergeA");
426 
427   /** The upper-half merge region column qualifier */
428   public static final byte[] MERGEB_QUALIFIER = Bytes.toBytes("mergeB");
429 
430   /**
431    * The meta table version column qualifier.
432    * We keep current version of the meta table in this column in <code>-ROOT-</code>
433    * table: i.e. in the 'info:v' column.
434    */
435   public static final byte [] META_VERSION_QUALIFIER = Bytes.toBytes("v");
436 
437   /**
438    * The current version of the meta table.
439    * - pre-hbase 0.92.  There is no META_VERSION column in the root table
440    * in this case. The meta has HTableDescriptor serialized into the HRegionInfo;
441    * - version 0 is 0.92 and 0.94. Meta data has serialized HRegionInfo's using
442    * Writable serialization, and HRegionInfo's does not contain HTableDescriptors.
443    * - version 1 for 0.96+ keeps HRegionInfo data structures, but changes the
444    * byte[] serialization from Writables to Protobuf.
445    * See HRegionInfo.VERSION
446    */
447   public static final short META_VERSION = 1;
448 
449   // Other constants
450 
451   /**
452    * An empty instance.
453    */
454   public static final byte [] EMPTY_BYTE_ARRAY = new byte [0];
455 
456   /**
457    * Used by scanners, etc when they want to start at the beginning of a region
458    */
459   public static final byte [] EMPTY_START_ROW = EMPTY_BYTE_ARRAY;
460 
461   /**
462    * Last row in a table.
463    */
464   public static final byte [] EMPTY_END_ROW = EMPTY_START_ROW;
465 
466   /**
467     * Used by scanners and others when they're trying to detect the end of a
468     * table
469     */
470   public static final byte [] LAST_ROW = EMPTY_BYTE_ARRAY;
471 
472   /**
473    * Max length a row can have because of the limitation in TFile.
474    */
475   public static final int MAX_ROW_LENGTH = Short.MAX_VALUE;
476 
477   /**
478    * Timestamp to use when we want to refer to the latest cell.
479    * This is the timestamp sent by clients when no timestamp is specified on
480    * commit.
481    */
482   public static final long LATEST_TIMESTAMP = Long.MAX_VALUE;
483 
484   /**
485    * Timestamp to use when we want to refer to the oldest cell.
486    */
487   public static final long OLDEST_TIMESTAMP = Long.MIN_VALUE;
488 
489   /**
490    * LATEST_TIMESTAMP in bytes form
491    */
492   public static final byte [] LATEST_TIMESTAMP_BYTES = {
493     // big-endian
494     (byte) (LATEST_TIMESTAMP >>> 56),
495     (byte) (LATEST_TIMESTAMP >>> 48),
496     (byte) (LATEST_TIMESTAMP >>> 40),
497     (byte) (LATEST_TIMESTAMP >>> 32),
498     (byte) (LATEST_TIMESTAMP >>> 24),
499     (byte) (LATEST_TIMESTAMP >>> 16),
500     (byte) (LATEST_TIMESTAMP >>> 8),
501     (byte) LATEST_TIMESTAMP,
502   };
503 
504   /**
505    * Define for 'return-all-versions'.
506    */
507   public static final int ALL_VERSIONS = Integer.MAX_VALUE;
508 
509   /**
510    * Unlimited time-to-live.
511    */
512 //  public static final int FOREVER = -1;
513   public static final int FOREVER = Integer.MAX_VALUE;
514 
515   /**
516    * Seconds in a week
517    */
518   public static final int WEEK_IN_SECONDS = 7 * 24 * 3600;
519 
520   /**
521    * Seconds in a day, hour and minute
522    */
523   public static final int DAY_IN_SECONDS = 24 * 60 * 60;
524   public static final int HOUR_IN_SECONDS = 60 * 60;
525   public static final int MINUTE_IN_SECONDS = 60;
526 
527   //TODO: although the following are referenced widely to format strings for
528   //      the shell. They really aren't a part of the public API. It would be
529   //      nice if we could put them somewhere where they did not need to be
530   //      public. They could have package visibility
531   public static final String NAME = "NAME";
532   public static final String VERSIONS = "VERSIONS";
533   public static final String IN_MEMORY = "IN_MEMORY";
534   public static final String METADATA = "METADATA";
535   public static final String CONFIGURATION = "CONFIGURATION";
536 
537   /**
538    * Retrying we multiply hbase.client.pause setting by what we have in this array until we
539    * run out of array items.  Retries beyond this use the last number in the array.  So, for
540    * example, if hbase.client.pause is 1 second, and maximum retries count
541    * hbase.client.retries.number is 10, we will retry at the following intervals:
542    * 1, 2, 3, 5, 10, 20, 40, 100, 100, 100.
543    * With 100ms, a back-off of 200 means 20s
544    */
545   public static int RETRY_BACKOFF[] = { 1, 2, 3, 5, 10, 20, 40, 100, 100, 100, 100, 200, 200 };
546 
547   public static final String REGION_IMPL = "hbase.hregion.impl";
548 
549   /** modifyTable op for replacing the table descriptor */
550   public static enum Modify {
551     CLOSE_REGION,
552     TABLE_COMPACT,
553     TABLE_FLUSH,
554     TABLE_MAJOR_COMPACT,
555     TABLE_SET_HTD,
556     TABLE_SPLIT
557   }
558 
559   /**
560    * Scope tag for locally scoped data.
561    * This data will not be replicated.
562    */
563   public static final int REPLICATION_SCOPE_LOCAL = 0;
564 
565   /**
566    * Scope tag for globally scoped data.
567    * This data will be replicated to all peers.
568    */
569   public static final int REPLICATION_SCOPE_GLOBAL = 1;
570 
571   /**
572    * Default cluster ID, cannot be used to identify a cluster so a key with
573    * this value means it wasn't meant for replication.
574    */
575   public static final UUID DEFAULT_CLUSTER_ID = new UUID(0L,0L);
576 
577     /**
578      * Parameter name for maximum number of bytes returned when calling a
579      * scanner's next method.
580      */
581   public static String HBASE_CLIENT_SCANNER_MAX_RESULT_SIZE_KEY = "hbase.client.scanner.max.result.size";
582 
583   /**
584    * Maximum number of bytes returned when calling a scanner's next method.
585    * Note that when a single row is larger than this limit the row is still
586    * returned completely.
587    *
588    * The default value is unlimited.
589    */
590   public static long DEFAULT_HBASE_CLIENT_SCANNER_MAX_RESULT_SIZE = Long.MAX_VALUE;
591 
592   /**
593    * Parameter name for client pause value, used mostly as value to wait
594    * before running a retry of a failed get, region lookup, etc.
595    */
596   public static String HBASE_CLIENT_PAUSE = "hbase.client.pause";
597 
598   /**
599    * Default value of {@link #HBASE_CLIENT_PAUSE}.
600    */
601   public static long DEFAULT_HBASE_CLIENT_PAUSE = 100;
602 
603   /**
604    * The maximum number of concurrent connections the client will maintain.
605    */
606   public static final String HBASE_CLIENT_MAX_TOTAL_TASKS = "hbase.client.max.total.tasks";
607 
608   /**
609    * Default value of {@link #HBASE_CLIENT_MAX_TOTAL_TASKS}.
610    */
611   public static final int DEFAULT_HBASE_CLIENT_MAX_TOTAL_TASKS = 100;
612 
613   /**
614    * The maximum number of concurrent connections the client will maintain to a single
615    * RegionServer.
616    */
617   public static final String HBASE_CLIENT_MAX_PERSERVER_TASKS = "hbase.client.max.perserver.tasks";
618 
619   /**
620    * Default value of {@link #HBASE_CLIENT_MAX_PERSERVER_TASKS}.
621    */
622   public static final int DEFAULT_HBASE_CLIENT_MAX_PERSERVER_TASKS = 2;
623 
624   /**
625    * The maximum number of concurrent connections the client will maintain to a single
626    * Region.
627    */
628   public static final String HBASE_CLIENT_MAX_PERREGION_TASKS = "hbase.client.max.perregion.tasks";
629 
630   /**
631    * Default value of {@link #HBASE_CLIENT_MAX_PERREGION_TASKS}.
632    */
633   public static final int DEFAULT_HBASE_CLIENT_MAX_PERREGION_TASKS = 1;
634 
635   /**
636    * Parameter name for server pause value, used mostly as value to wait before
637    * running a retry of a failed operation.
638    */
639   public static String HBASE_SERVER_PAUSE = "hbase.server.pause";
640 
641   /**
642    * Default value of {@link #HBASE_SERVER_PAUSE}.
643    */
644   public static int DEFAULT_HBASE_SERVER_PAUSE = 1000;
645 
646   /**
647    * Parameter name for maximum retries, used as maximum for all retryable
648    * operations such as fetching of the root region from root region server,
649    * getting a cell's value, starting a row update, etc.
650    */
651   public static String HBASE_CLIENT_RETRIES_NUMBER = "hbase.client.retries.number";
652 
653   /**
654    * Default value of {@link #HBASE_CLIENT_RETRIES_NUMBER}.
655    */
656   public static int DEFAULT_HBASE_CLIENT_RETRIES_NUMBER = 31;
657 
658   /**
659    * Parameter name to set the default scanner caching for all clients.
660    */
661   public static String HBASE_CLIENT_SCANNER_CACHING = "hbase.client.scanner.caching";
662 
663   /**
664    * Default value for {@link #HBASE_CLIENT_SCANNER_CACHING}
665    */
666   public static int DEFAULT_HBASE_CLIENT_SCANNER_CACHING = 100;
667 
668   /**
669    * Parameter name for number of rows that will be fetched when calling next on
670    * a scanner if it is not served from memory. Higher caching values will
671    * enable faster scanners but will eat up more memory and some calls of next
672    * may take longer and longer times when the cache is empty.
673    */
674   public static String HBASE_META_SCANNER_CACHING = "hbase.meta.scanner.caching";
675 
676   /**
677    * Default value of {@link #HBASE_META_SCANNER_CACHING}.
678    */
679   public static int DEFAULT_HBASE_META_SCANNER_CACHING = 100;
680 
681   /**
682    * Parameter name for unique identifier for this {@link org.apache.hadoop.conf.Configuration}
683    * instance. If there are two or more {@link org.apache.hadoop.conf.Configuration} instances that,
684    * for all intents and purposes, are the same except for their instance ids, then they will not be
685    * able to share the same org.apache.hadoop.hbase.client.HConnection instance. On the other hand,
686    * even if the instance ids are the same, it could result in non-shared
687    * org.apache.hadoop.hbase.client.HConnection instances if some of the other connection parameters
688    * differ.
689    */
690   public static String HBASE_CLIENT_INSTANCE_ID = "hbase.client.instance.id";
691 
692   /**
693    * The client scanner timeout period in milliseconds.
694    */
695   public static String HBASE_CLIENT_SCANNER_TIMEOUT_PERIOD = "hbase.client.scanner.timeout.period";
696 
697   /**
698    * Use {@link #HBASE_CLIENT_SCANNER_TIMEOUT_PERIOD} instead.
699    * @deprecated This config option is deprecated. Will be removed at later releases after 0.96.
700    */
701   @Deprecated
702   public static String HBASE_REGIONSERVER_LEASE_PERIOD_KEY =
703       "hbase.regionserver.lease.period";
704 
705   /**
706    * Default value of {@link #HBASE_CLIENT_SCANNER_TIMEOUT_PERIOD}.
707    */
708   public static int DEFAULT_HBASE_CLIENT_SCANNER_TIMEOUT_PERIOD = 60000;
709 
710   /**
711    * timeout for each RPC
712    */
713   public static String HBASE_RPC_TIMEOUT_KEY = "hbase.rpc.timeout";
714 
715   /**
716    * Default value of {@link #HBASE_RPC_TIMEOUT_KEY}
717    */
718   public static int DEFAULT_HBASE_RPC_TIMEOUT = 60000;
719 
720   /**
721    * timeout for short operation RPC
722    */
723   public static String HBASE_RPC_SHORTOPERATION_TIMEOUT_KEY = "hbase.rpc.shortoperation.timeout";
724 
725   /**
726    * Default value of {@link #HBASE_RPC_SHORTOPERATION_TIMEOUT_KEY}
727    */
728   public static int DEFAULT_HBASE_RPC_SHORTOPERATION_TIMEOUT = 10000;
729 
730   /**
731    * Value indicating the server name was saved with no sequence number.
732    */
733   public static final long NO_SEQNUM = -1;
734 
735 
736   /*
737    * cluster replication constants.
738    */
739   public static final String
740       REPLICATION_ENABLE_KEY = "hbase.replication";
741   public static final boolean
742       REPLICATION_ENABLE_DEFAULT = true;
743   public static final String
744       REPLICATION_SOURCE_SERVICE_CLASSNAME = "hbase.replication.source.service";
745   public static final String
746       REPLICATION_SINK_SERVICE_CLASSNAME = "hbase.replication.sink.service";
747   public static final String REPLICATION_SERVICE_CLASSNAME_DEFAULT =
748     "org.apache.hadoop.hbase.replication.regionserver.Replication";
749 
750   /** HBCK special code name used as server name when manipulating ZK nodes */
751   public static final String HBCK_CODE_NAME = "HBCKServerName";
752 
753   public static final String KEY_FOR_HOSTNAME_SEEN_BY_MASTER =
754     "hbase.regionserver.hostname.seen.by.master";
755 
756   public static final String HBASE_MASTER_LOGCLEANER_PLUGINS =
757       "hbase.master.logcleaner.plugins";
758 
759   public static final String HBASE_REGION_SPLIT_POLICY_KEY =
760     "hbase.regionserver.region.split.policy";
761 
762   /** Whether nonces are enabled; default is true. */
763   public static String HBASE_RS_NONCES_ENABLED = "hbase.regionserver.nonces.enabled";
764 
765   /**
766    * Configuration key for the size of the block cache
767    */
768   public static final String HFILE_BLOCK_CACHE_SIZE_KEY =
769     "hfile.block.cache.size";
770 
771   public static final float HFILE_BLOCK_CACHE_SIZE_DEFAULT = 0.4f;
772 
773   /*
774     * Minimum percentage of free heap necessary for a successful cluster startup.
775     */
776   public static final float HBASE_CLUSTER_MINIMUM_MEMORY_THRESHOLD = 0.2f;
777 
778   public static final Pattern CP_HTD_ATTR_KEY_PATTERN = Pattern.compile
779       ("^coprocessor\\$([0-9]+)$", Pattern.CASE_INSENSITIVE);
780   public static final Pattern CP_HTD_ATTR_VALUE_PATTERN =
781       Pattern.compile("(^[^\\|]*)\\|([^\\|]+)\\|[\\s]*([\\d]*)[\\s]*(\\|.*)?$");
782 
783   public static final String CP_HTD_ATTR_VALUE_PARAM_KEY_PATTERN = "[^=,]+";
784   public static final String CP_HTD_ATTR_VALUE_PARAM_VALUE_PATTERN = "[^,]+";
785   public static final Pattern CP_HTD_ATTR_VALUE_PARAM_PATTERN = Pattern.compile(
786       "(" + CP_HTD_ATTR_VALUE_PARAM_KEY_PATTERN + ")=(" +
787       CP_HTD_ATTR_VALUE_PARAM_VALUE_PATTERN + "),?");
788 
789   /** The delay when re-trying a socket operation in a loop (HBASE-4712) */
790   public static final int SOCKET_RETRY_WAIT_MS = 200;
791 
792   /** Host name of the local machine */
793   public static final String LOCALHOST = "localhost";
794 
795   /**
796    * If this parameter is set to true, then hbase will read
797    * data and then verify checksums. Checksum verification
798    * inside hdfs will be switched off.  However, if the hbase-checksum
799    * verification fails, then it will switch back to using
800    * hdfs checksums for verifiying data that is being read from storage.
801    *
802    * If this parameter is set to false, then hbase will not
803    * verify any checksums, instead it will depend on checksum verification
804    * being done in the hdfs client.
805    */
806   public static final String HBASE_CHECKSUM_VERIFICATION =
807       "hbase.regionserver.checksum.verify";
808 
809   public static final String LOCALHOST_IP = "127.0.0.1";
810 
811   /** Conf key that enables unflushed WAL edits directly being replayed to region servers */
812   public static final String DISTRIBUTED_LOG_REPLAY_KEY = "hbase.master.distributed.log.replay";
813   /**
814    * Default 'distributed log replay' as true since hbase 0.99.0
815    */
816   public static final boolean DEFAULT_DISTRIBUTED_LOG_REPLAY_CONFIG = true;
817   public static final String DISALLOW_WRITES_IN_RECOVERING =
818       "hbase.regionserver.disallow.writes.when.recovering";
819   public static final boolean DEFAULT_DISALLOW_WRITES_IN_RECOVERING_CONFIG = false;
820 
821   public static final String REGION_SERVER_HANDLER_COUNT = "hbase.regionserver.handler.count";
822   public static final int DEFAULT_REGION_SERVER_HANDLER_COUNT = 30;
823 
824   public static final String REGION_SERVER_META_HANDLER_COUNT =
825       "hbase.regionserver.metahandler.count";
826   public static final int DEFAULT_REGION_SERVER_META_HANDLER_COUNT = 10;
827 
828   public static final String REGION_SERVER_REPLICATION_HANDLER_COUNT =
829       "hbase.regionserver.replication.handler.count";
830   public static final int DEFAULT_REGION_SERVER_REPLICATION_HANDLER_COUNT = 3;
831 
832   public static final String MASTER_HANDLER_COUNT = "hbase.master.handler.count";
833   public static final int DEFAULT_MASTER_HANLDER_COUNT = 25;
834 
835   /** Conf key that specifies timeout value to wait for a region ready */
836   public static final String LOG_REPLAY_WAIT_REGION_TIMEOUT =
837       "hbase.master.log.replay.wait.region.timeout";
838 
839   /**
840    * The name of the configuration parameter that specifies
841    * the number of bytes in a newly created checksum chunk.
842    */
843   public static final String BYTES_PER_CHECKSUM =
844       "hbase.hstore.bytes.per.checksum";
845 
846   /**
847    * The name of the configuration parameter that specifies
848    * the name of an algorithm that is used to compute checksums
849    * for newly created blocks.
850    */
851   public static final String CHECKSUM_TYPE_NAME =
852       "hbase.hstore.checksum.algorithm";
853 
854   /** Enable file permission modification from standard hbase */
855   public static final String ENABLE_DATA_FILE_UMASK = "hbase.data.umask.enable";
856   /** File permission umask to use when creating hbase data files */
857   public static final String DATA_FILE_UMASK_KEY = "hbase.data.umask";
858 
859   /** Configuration name of HLog Compression */
860   public static final String ENABLE_WAL_COMPRESSION =
861     "hbase.regionserver.wal.enablecompression";
862 
863   /** Region in Transition metrics threshold time */
864   public static final String METRICS_RIT_STUCK_WARNING_THRESHOLD="hbase.metrics.rit.stuck.warning.threshold";
865 
866   public static final String LOAD_BALANCER_SLOP_KEY = "hbase.regions.slop";
867 
868   /**
869    * The byte array represents for NO_NEXT_INDEXED_KEY;
870    * The actual value is irrelevant because this is always compared by reference.
871    */
872   public static final byte [] NO_NEXT_INDEXED_KEY = Bytes.toBytes("NO_NEXT_INDEXED_KEY");
873   /** delimiter used between portions of a region name */
874   public static final int DELIMITER = ',';
875   public static final String HBASE_CONFIG_READ_ZOOKEEPER_CONFIG =
876       "hbase.config.read.zookeeper.config";
877   public static final boolean DEFAULT_HBASE_CONFIG_READ_ZOOKEEPER_CONFIG =
878       false;
879 
880   /**
881    * QOS attributes: these attributes are used to demarcate RPC call processing
882    * by different set of handlers. For example, HIGH_QOS tagged methods are
883    * handled by high priority handlers.
884    */
885   public static final int NORMAL_QOS = 0;
886   public static final int QOS_THRESHOLD = 10;
887   public static final int HIGH_QOS = 100;
888   public static final int REPLICATION_QOS = 5; // normal_QOS < replication_QOS < high_QOS
889   public static final int REPLAY_QOS = 6; // REPLICATION_QOS < REPLAY_QOS < high_QOS
890 
891   /** Directory under /hbase where archived hfiles are stored */
892   public static final String HFILE_ARCHIVE_DIRECTORY = "archive";
893 
894   /**
895    * Name of the directory to store all snapshots. See SnapshotDescriptionUtils for
896    * remaining snapshot constants; this is here to keep HConstants dependencies at a minimum and
897    * uni-directional.
898    */
899   public static final String SNAPSHOT_DIR_NAME = ".hbase-snapshot";
900 
901   /* Name of old snapshot directory. See HBASE-8352 for details on why it needs to be renamed */
902   public static final String OLD_SNAPSHOT_DIR_NAME = ".snapshot";
903 
904   /** Temporary directory used for table creation and deletion */
905   public static final String HBASE_TEMP_DIRECTORY = ".tmp";
906   /**
907    * The period (in milliseconds) between computing region server point in time metrics
908    */
909   public static final String REGIONSERVER_METRICS_PERIOD = "hbase.regionserver.metrics.period";
910   public static final long DEFAULT_REGIONSERVER_METRICS_PERIOD = 5000;
911   /** Directories that are not HBase table directories */
912   public static final List<String> HBASE_NON_TABLE_DIRS =
913     Collections.unmodifiableList(Arrays.asList(new String[] { HREGION_LOGDIR_NAME,
914       HREGION_OLDLOGDIR_NAME, CORRUPT_DIR_NAME, SPLIT_LOGDIR_NAME,
915       HBCK_SIDELINEDIR_NAME, HFILE_ARCHIVE_DIRECTORY, SNAPSHOT_DIR_NAME, HBASE_TEMP_DIRECTORY,
916       OLD_SNAPSHOT_DIR_NAME, BASE_NAMESPACE_DIR, MIGRATION_NAME, LIB_DIR}));
917 
918   /** Directories that are not HBase user table directories */
919   public static final List<String> HBASE_NON_USER_TABLE_DIRS =
920     Collections.unmodifiableList(Arrays.asList((String[])ArrayUtils.addAll(
921       new String[] { TableName.META_TABLE_NAME.getNameAsString() },
922       HBASE_NON_TABLE_DIRS.toArray())));
923 
924   /** Health script related settings. */
925   public static final String HEALTH_SCRIPT_LOC = "hbase.node.health.script.location";
926   public static final String HEALTH_SCRIPT_TIMEOUT = "hbase.node.health.script.timeout";
927   public static final String HEALTH_CHORE_WAKE_FREQ =
928       "hbase.node.health.script.frequency";
929   public static final long DEFAULT_HEALTH_SCRIPT_TIMEOUT = 60000;
930   /**
931    * The maximum number of health check failures a server can encounter consecutively.
932    */
933   public static final String HEALTH_FAILURE_THRESHOLD =
934       "hbase.node.health.failure.threshold";
935   public static final int DEFAULT_HEALTH_FAILURE_THRESHOLD = 3;
936 
937 
938   /**
939    * Setting to activate, or not, the publication of the status by the master. Default
940    *  notification is by a multicast message.
941    */
942   public static final String STATUS_PUBLISHED = "hbase.status.published";
943   public static final boolean STATUS_PUBLISHED_DEFAULT = false;
944 
945   /**
946    * IP to use for the multicast status messages between the master and the clients.
947    * The default address is chosen as one among others within the ones suitable for multicast
948    * messages.
949    */
950   public static final String STATUS_MULTICAST_ADDRESS = "hbase.status.multicast.address.ip";
951   public static final String DEFAULT_STATUS_MULTICAST_ADDRESS = "226.1.1.3";
952 
953   /**
954    * The address to use for binding the local socket for receiving multicast. Defaults to
955    * 0.0.0.0.
956    * @see <a href="https://issues.apache.org/jira/browse/HBASE-9961">HBASE-9961</a>
957    */
958   public static final String STATUS_MULTICAST_BIND_ADDRESS = "hbase.status.multicast.bind.address.ip";
959   public static final String DEFAULT_STATUS_MULTICAST_BIND_ADDRESS = "0.0.0.0";
960 
961   /**
962    * The port to use for the multicast messages.
963    */
964   public static final String STATUS_MULTICAST_PORT = "hbase.status.multicast.address.port";
965   public static final int DEFAULT_STATUS_MULTICAST_PORT = 16100;
966 
967   public static final long NO_NONCE = 0;
968 
969   /** Configuration key for the crypto algorithm provider, a class name */
970   public static final String CRYPTO_CIPHERPROVIDER_CONF_KEY = "hbase.crypto.cipherprovider";
971 
972   /** Configuration key for the crypto key provider, a class name */
973   public static final String CRYPTO_KEYPROVIDER_CONF_KEY = "hbase.crypto.keyprovider";
974 
975   /** Configuration key for the crypto key provider parameters */
976   public static final String CRYPTO_KEYPROVIDER_PARAMETERS_KEY =
977       "hbase.crypto.keyprovider.parameters";
978 
979   /** Configuration key for the name of the master key for the cluster, a string */
980   public static final String CRYPTO_MASTERKEY_NAME_CONF_KEY = "hbase.crypto.master.key.name";
981 
982   /** Configuration key for the name of the alternate master key for the cluster, a string */
983   public static final String CRYPTO_MASTERKEY_ALTERNATE_NAME_CONF_KEY =
984     "hbase.crypto.master.alternate.key.name";
985 
986   /** Configuration key for the algorithm to use when encrypting the WAL, a string */
987   public static final String CRYPTO_WAL_ALGORITHM_CONF_KEY = "hbase.crypto.wal.algorithm";
988 
989   /** Configuration key for the name of the master WAL encryption key for the cluster, a string */
990   public static final String CRYPTO_WAL_KEY_NAME_CONF_KEY = "hbase.crypto.wal.key.name";
991 
992   /** Configuration key for enabling HLog encryption, a boolean */
993   public static final String ENABLE_WAL_ENCRYPTION = "hbase.regionserver.wal.encryption";
994 
995   /** Configuration key for setting RPC codec class name */
996   public static final String RPC_CODEC_CONF_KEY = "hbase.client.rpc.codec";
997 
998   /** Configuration key for setting replication codec class name */
999   public static final String REPLICATION_CODEC_CONF_KEY = "hbase.replication.rpc.codec";
1000 
1001   /** Config for pluggable consensus provider */
1002   public static final String HBASE_COORDINATED_STATE_MANAGER_CLASS =
1003     "hbase.coordinated.state.manager.class";
1004 
1005   private HConstants() {
1006     // Can't be instantiated with this ctor.
1007   }
1008 }