ReplicationSink (Apache HBase 1.2.12 API)

java.lang.Object
- org.apache.hadoop.hbase.replication.regionserver.ReplicationSink

```
@InterfaceAudience.Private
public class ReplicationSink
extends Object
```
This class is responsible for replicating the edits coming from another cluster.
This replication process is currently waiting for the edits to be applied before the method can return. This means that the replication of edits is synchronized (after reading from WALs in ReplicationSource) and that a single region server cannot receive edits from two sources at the same time
This class uses the native HBase client in order to replicate entries.
TODO make this class more like ReplicationSource wrt log handling

Field Summary

Fields
Modifier and Type	Field and Description
`private org.apache.hadoop.conf.Configuration`	`conf`
`private static org.apache.commons.logging.Log`	`LOG`
`private MetricsSink`	`metrics`
`private Connection`	`sharedHtableCon`
`private Object`	`sharedHtableConLock`
`private AtomicLong`	`totalReplicatedEdits`

Constructor Summary

Constructors
Constructor and Description

ReplicationSink(org.apache.hadoop.conf.Configuration conf, Stoppable stopper)
Create a sink for replication

Constructors
Constructor and Description
`ReplicationSink(org.apache.hadoop.conf.Configuration conf, Stoppable stopper)` Create a sink for replication

Method Summary

Methods
Modifier and Type	Method and Description
`private <K1,K2,V> List<V>`	`addToHashMultiMap(Map<K1,Map<K2,List<V>>> map, K1 key1, K2 key2, V value)` Simple helper to a map from key to (a list of) values TODO: Make a general utility method
`protected void`	`batch(TableName tableName, Collection<List<Row>> allRows)` Do the changes and handle the pool
`private void`	`decorateConf()` decorate the Configuration object to make replication more receptive to delays: lessen the timeout and numTries.
`MetricsSink`	`getSinkMetrics()` Get replication Sink Metrics
`String`	`getStats()` Get a string representation of this sink's metrics
`private boolean`	`isNewRowOrType(Cell previousCell, Cell cell)`
`void`	`replicateEntries(List<org.apache.hadoop.hbase.protobuf.generated.AdminProtos.WALEntry> entries, CellScanner cells)` Replicate this array of entries directly into the local cluster using the native client.
`void`	`stopReplicationSinkServices()` stop the thread pool executor.
`private UUID`	`toUUID(org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.UUID uuid)`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - LOG
```
private static final org.apache.commons.logging.Log LOG
```
  - conf
```
private final org.apache.hadoop.conf.Configuration conf
```
  - sharedHtableCon
```
private volatile Connection sharedHtableCon
```
  - metrics
```
private final MetricsSink metrics
```
  - totalReplicatedEdits
```
private final AtomicLong totalReplicatedEdits
```
  - sharedHtableConLock
```
private final Object sharedHtableConLock
```
- Constructor Detail
  - ReplicationSink
```
public ReplicationSink(org.apache.hadoop.conf.Configuration conf,
               Stoppable stopper)
                throws IOException
```
    Create a sink for replication
    
    Parameters:
    conf - conf object
    stopper - boolean to tell this thread to stop
    
    Throws:
    
    IOException - thrown when HDFS goes bad or bad file name
- Method Detail
  - decorateConf
```
private void decorateConf()
```
    decorate the Configuration object to make replication more receptive to delays: lessen the timeout and numTries.
  - replicateEntries
```
public void replicateEntries(List<org.apache.hadoop.hbase.protobuf.generated.AdminProtos.WALEntry> entries,
                    CellScanner cells)
                      throws IOException
```
    Replicate this array of entries directly into the local cluster using the native client. Only operates against raw protobuf type saving on a conversion from pb to pojo.
    
    Parameters:
    entries -
    cells -
    
    Throws:
    
    IOException
  - isNewRowOrType
```
private boolean isNewRowOrType(Cell previousCell,
                     Cell cell)
```
    Parameters:
    previousCell -
    cell -
    
    Returns:
    True if we have crossed over onto a new row or type
  - toUUID
```
private UUID toUUID(org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.UUID uuid)
```
  - addToHashMultiMap
```
private <K1,K2,V> List<V> addToHashMultiMap(Map<K1,Map<K2,List<V>>> map,
                                  K1 key1,
                                  K2 key2,
                                  V value)
```
    Simple helper to a map from key to (a list of) values TODO: Make a general utility method
    
    Parameters:
    map -
    key1 -
    key2 -
    value -
    
    Returns:
    the list of values corresponding to key1 and key2
  - stopReplicationSinkServices
```
public void stopReplicationSinkServices()
```
    stop the thread pool executor. It is called when the regionserver is stopped.
  - batch
```
protected void batch(TableName tableName,
         Collection<List<Row>> allRows)
              throws IOException
```
    Do the changes and handle the pool
    
    Parameters:
    tableName - table to insert into
    allRows - list of actions
    
    Throws:
    
    IOException
  - getStats
```
public String getStats()
```
    Get a string representation of this sink's metrics
    
    Returns:
    string with the total replicated edits count and the date of the last edit that was applied
  - getSinkMetrics
```
public MetricsSink getSinkMetrics()
```
    Get replication Sink Metrics
    
    Returns:
    MetricsSink

Class ReplicationSink

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

LOG

conf

sharedHtableCon

metrics

totalReplicatedEdits

sharedHtableConLock

Constructor Detail

ReplicationSink

Method Detail

decorateConf

replicateEntries

isNewRowOrType

toUUID

addToHashMultiMap

stopReplicationSinkServices

batch

getStats

getSinkMetrics