BaseRegionServerObserver (Apache HBase 1.2.12 API)

java.lang.Object
- org.apache.hadoop.hbase.coprocessor.BaseRegionServerObserver

All Implemented Interfaces:

Coprocessor, RegionServerObserver

Direct Known Subclasses:

VisibilityController.VisibilityReplication
```
@InterfaceAudience.LimitedPrivate(value="Coprocesssor")
@InterfaceStability.Evolving
public class BaseRegionServerObserver
extends Object
implements RegionServerObserver
```
An abstract class that implements RegionServerObserver. By extending it, you can create your own region server observer without overriding all abstract methods of RegionServerObserver.

Nested Class Summary
- Nested classes/interfaces inherited from interface org.apache.hadoop.hbase.Coprocessor
  Coprocessor.State

Field Summary
- Fields inherited from interface org.apache.hadoop.hbase.Coprocessor
  PRIORITY_HIGHEST, PRIORITY_LOWEST, PRIORITY_SYSTEM, PRIORITY_USER, VERSION

Constructor Summary

Constructors
Constructor and Description

BaseRegionServerObserver()

Constructors
Constructor and Description
`BaseRegionServerObserver()`

Method Summary

Methods
Modifier and Type	Method and Description
`ReplicationEndpoint`	`postCreateReplicationEndPoint(ObserverContext<RegionServerCoprocessorEnvironment> ctx, ReplicationEndpoint endpoint)` This will be called after the replication endpoint is instantiated.
`void`	`postMerge(ObserverContext<RegionServerCoprocessorEnvironment> c, Region regionA, Region regionB, Region mergedRegion)` called after the regions merge.
`void`	`postMergeCommit(ObserverContext<RegionServerCoprocessorEnvironment> ctx, Region regionA, Region regionB, Region mergedRegion)` This will be called after PONR step as part of regions merge transaction.
`void`	`postReplicateLogEntries(ObserverContext<RegionServerCoprocessorEnvironment> ctx, List<org.apache.hadoop.hbase.protobuf.generated.AdminProtos.WALEntry> entries, CellScanner cells)` This will be called after executing replication request to shipping log entries.
`void`	`postRollBackMerge(ObserverContext<RegionServerCoprocessorEnvironment> ctx, Region regionA, Region regionB)` This will be called after the roll back of the regions merge.
`void`	`postRollWALWriterRequest(ObserverContext<RegionServerCoprocessorEnvironment> ctx)` This will be called after executing user request to roll a region server WAL.
`void`	`preMerge(ObserverContext<RegionServerCoprocessorEnvironment> ctx, Region regionA, Region regionB)` Called before the regions merge.
`void`	`preMergeCommit(ObserverContext<RegionServerCoprocessorEnvironment> ctx, Region regionA, Region regionB, List<Mutation> metaEntries)` This will be called before PONR step as part of regions merge transaction.
`void`	`preReplicateLogEntries(ObserverContext<RegionServerCoprocessorEnvironment> ctx, List<org.apache.hadoop.hbase.protobuf.generated.AdminProtos.WALEntry> entries, CellScanner cells)` This will be called before executing replication request to shipping log entries.
`void`	`preRollBackMerge(ObserverContext<RegionServerCoprocessorEnvironment> ctx, Region regionA, Region regionB)` This will be called before the roll back of the regions merge.
`void`	`preRollWALWriterRequest(ObserverContext<RegionServerCoprocessorEnvironment> ctx)` This will be called before executing user request to roll a region server WAL.
`void`	`preStopRegionServer(ObserverContext<RegionServerCoprocessorEnvironment> env)` Called before stopping region server.
`void`	`start(CoprocessorEnvironment env)`
`void`	`stop(CoprocessorEnvironment env)`

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

- Constructor Detail
  - BaseRegionServerObserver
```
public BaseRegionServerObserver()
```
- Method Detail
  - preStopRegionServer
```
public void preStopRegionServer(ObserverContext<RegionServerCoprocessorEnvironment> env)
                         throws IOException
```
    Description copied from interface: RegionServerObserver
    
    Called before stopping region server.
    
    Specified by:
    
    preStopRegionServer in interface RegionServerObserver
    
    Parameters:
    env - An instance of RegionServerCoprocessorEnvironment
    
    Throws:
    
    IOException - Signals that an I/O exception has occurred.
  - start
```
public void start(CoprocessorEnvironment env)
           throws IOException
```
    Specified by:
    
    start in interface Coprocessor
    
    Throws:
    
    IOException
  - stop
```
public void stop(CoprocessorEnvironment env)
          throws IOException
```
    Specified by:
    
    stop in interface Coprocessor
    
    Throws:
    
    IOException
  - preMerge
```
public void preMerge(ObserverContext<RegionServerCoprocessorEnvironment> ctx,
            Region regionA,
            Region regionB)
              throws IOException
```
    Description copied from interface: RegionServerObserver
    
    Called before the regions merge. Call ObserverContext.bypass() to skip the merge.
    
    Specified by:
    
    preMerge in interface RegionServerObserver
    
    Throws:
    
    IOException - if an error occurred on the coprocessor
  - postMerge
```
public void postMerge(ObserverContext<RegionServerCoprocessorEnvironment> c,
             Region regionA,
             Region regionB,
             Region mergedRegion)
               throws IOException
```
    Description copied from interface: RegionServerObserver
    
    called after the regions merge.
    
    Specified by:
    
    postMerge in interface RegionServerObserver
    
    Throws:
    
    IOException
  - preMergeCommit
```
public void preMergeCommit(ObserverContext<RegionServerCoprocessorEnvironment> ctx,
                  Region regionA,
                  Region regionB,
                  List<Mutation> metaEntries)
                    throws IOException
```
    Description copied from interface: RegionServerObserver
    
    This will be called before PONR step as part of regions merge transaction. Calling ObserverContext.bypass() rollback the merge
    
    Specified by:
    
    preMergeCommit in interface RegionServerObserver
    
    metaEntries - mutations to execute on hbase:meta atomically with regions merge updates. Any puts or deletes to execute on hbase:meta can be added to the mutations.
    
    Throws:
    
    IOException
  - postMergeCommit
```
public void postMergeCommit(ObserverContext<RegionServerCoprocessorEnvironment> ctx,
                   Region regionA,
                   Region regionB,
                   Region mergedRegion)
                     throws IOException
```
    Description copied from interface: RegionServerObserver
    
    This will be called after PONR step as part of regions merge transaction.
    
    Specified by:
    
    postMergeCommit in interface RegionServerObserver
    
    Throws:
    
    IOException
  - preRollBackMerge
```
public void preRollBackMerge(ObserverContext<RegionServerCoprocessorEnvironment> ctx,
                    Region regionA,
                    Region regionB)
                      throws IOException
```
    Description copied from interface: RegionServerObserver
    
    This will be called before the roll back of the regions merge.
    
    Specified by:
    
    preRollBackMerge in interface RegionServerObserver
    
    Throws:
    
    IOException
  - postRollBackMerge
```
public void postRollBackMerge(ObserverContext<RegionServerCoprocessorEnvironment> ctx,
                     Region regionA,
                     Region regionB)
                       throws IOException
```
    Description copied from interface: RegionServerObserver
    
    This will be called after the roll back of the regions merge.
    
    Specified by:
    
    postRollBackMerge in interface RegionServerObserver
    
    Throws:
    
    IOException
  - preRollWALWriterRequest
```
public void preRollWALWriterRequest(ObserverContext<RegionServerCoprocessorEnvironment> ctx)
                             throws IOException
```
    Description copied from interface: RegionServerObserver
    
    This will be called before executing user request to roll a region server WAL.
    
    Specified by:
    
    preRollWALWriterRequest in interface RegionServerObserver
    
    Parameters:
    ctx - An instance of ObserverContext
    
    Throws:
    
    IOException - Signals that an I/O exception has occurred.
  - postRollWALWriterRequest
```
public void postRollWALWriterRequest(ObserverContext<RegionServerCoprocessorEnvironment> ctx)
                              throws IOException
```
    Description copied from interface: RegionServerObserver
    
    This will be called after executing user request to roll a region server WAL.
    
    Specified by:
    
    postRollWALWriterRequest in interface RegionServerObserver
    
    Parameters:
    ctx - An instance of ObserverContext
    
    Throws:
    
    IOException - Signals that an I/O exception has occurred.
  - postCreateReplicationEndPoint
```
public ReplicationEndpoint postCreateReplicationEndPoint(ObserverContext<RegionServerCoprocessorEnvironment> ctx,
                                                ReplicationEndpoint endpoint)
```
    Description copied from interface: RegionServerObserver
    
    This will be called after the replication endpoint is instantiated.
    
    Specified by:
    
    postCreateReplicationEndPoint in interface RegionServerObserver
    
    endpoint - - the base endpoint for replication
    
    Returns:
    the endpoint to use during replication.
  - preReplicateLogEntries
```
public void preReplicateLogEntries(ObserverContext<RegionServerCoprocessorEnvironment> ctx,
                          List<org.apache.hadoop.hbase.protobuf.generated.AdminProtos.WALEntry> entries,
                          CellScanner cells)
                            throws IOException
```
    Description copied from interface: RegionServerObserver
    
    This will be called before executing replication request to shipping log entries.
    
    Specified by:
    
    preReplicateLogEntries in interface RegionServerObserver
    
    Parameters:
    ctx - An instance of ObserverContext
    entries - list of WALEntries to replicate
    cells - Cells that the WALEntries refer to (if cells is non-null)
    
    Throws:
    
    IOException - Signals that an I/O exception has occurred.
  - postReplicateLogEntries
```
public void postReplicateLogEntries(ObserverContext<RegionServerCoprocessorEnvironment> ctx,
                           List<org.apache.hadoop.hbase.protobuf.generated.AdminProtos.WALEntry> entries,
                           CellScanner cells)
                             throws IOException
```
    Description copied from interface: RegionServerObserver
    
    This will be called after executing replication request to shipping log entries.
    
    Specified by:
    
    postReplicateLogEntries in interface RegionServerObserver
    
    Parameters:
    ctx - An instance of ObserverContext
    entries - list of WALEntries to replicate
    cells - Cells that the WALEntries refer to (if cells is non-null)
    
    Throws:
    
    IOException - Signals that an I/O exception has occurred.

Class BaseRegionServerObserver

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.hadoop.hbase.Coprocessor

Field Summary

Fields inherited from interface org.apache.hadoop.hbase.Coprocessor

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

BaseRegionServerObserver

Method Detail

preStopRegionServer

start

stop

preMerge

postMerge

preMergeCommit

postMergeCommit

preRollBackMerge

postRollBackMerge

preRollWALWriterRequest

postRollWALWriterRequest

postCreateReplicationEndPoint

preReplicateLogEntries

postReplicateLogEntries