CloneSnapshotHandler (Apache HBase 1.2.12 API)

java.lang.Object
- org.apache.hadoop.hbase.executor.EventHandler
- - org.apache.hadoop.hbase.master.handler.CreateTableHandler
  - - org.apache.hadoop.hbase.master.snapshot.CloneSnapshotHandler

All Implemented Interfaces:

Comparable<Runnable>, Runnable, SnapshotSentinel
```
@InterfaceAudience.Private
public class CloneSnapshotHandler
extends CreateTableHandler
implements SnapshotSentinel
```
Handler to Clone a snapshot.
Uses RestoreSnapshotHelper to create a new table with the same content of the specified snapshot.

Nested Class Summary
- Nested classes/interfaces inherited from class org.apache.hadoop.hbase.executor.EventHandler
  EventHandler.EventHandlerListener

Field Summary

Fields
Modifier and Type	Field and Description
`private static org.apache.commons.logging.Log`	`LOG`
`private RestoreSnapshotHelper.RestoreMetaChanges`	`metaChanges`
`private MetricsSnapshot`	`metricsSnapshot`
`private ForeignExceptionDispatcher`	`monitor`
`private static String`	`NAME`
`private org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.SnapshotDescription`	`snapshot`
`private MonitoredTask`	`status`
`private boolean`	`stopped`

Fields inherited from class org.apache.hadoop.hbase.master.handler.CreateTableHandler
conf, fileSystemManager, hTableDescriptor

Fields inherited from class org.apache.hadoop.hbase.executor.EventHandler
eventType, seqids, server, waitingTimeForEvents

Constructor Summary

Constructors
Constructor and Description
`CloneSnapshotHandler(MasterServices masterServices, org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.SnapshotDescription snapshot, HTableDescriptor hTableDescriptor)`

Method Summary

Methods
Modifier and Type	Method and Description
`protected void`	`addRegionsToMeta(List<HRegionInfo> regionInfos, int regionReplication)` Add the specified set of regions to the hbase:meta table.
`void`	`cancel(String why)` Actively cancel a running snapshot.
`protected void`	`completed(Throwable exception)` Called after that process() is completed.
`long`	`getCompletionTimestamp()`
`ForeignException`	`getExceptionIfFailed()` Get the exception that caused the snapshot to fail, if the snapshot has failed.
`org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.SnapshotDescription`	`getSnapshot()`
`protected List<HRegionInfo>`	`handleCreateHdfsRegions(org.apache.hadoop.fs.Path tableRootDir, TableName tableName)` Create the on-disk regions, using the tableRootDir provided by the CreateTableHandler.
`boolean`	`isFinished()` Check to see if the snapshot is finished, where finished may be success or failure.
`CloneSnapshotHandler`	`prepare()` Event handlers should do all the necessary checks in this method (rather than in the constructor, or in process()) so that the caller, which is mostly executed in the ipc context can fail fast.
`void`	`rethrowExceptionIfFailed()` Rethrow the exception returned by `SnapshotSentinel.getExceptionIfFailed()`.

Methods inherited from class org.apache.hadoop.hbase.master.handler.CreateTableHandler
addReplicas, process, toString

Methods inherited from class org.apache.hadoop.hbase.executor.EventHandler
compareTo, getEventType, getInformativeName, getListener, getPriority, getSeqid, handleException, run, setListener

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

- Field Detail
  - LOG
```
private static final org.apache.commons.logging.Log LOG
```
  - NAME
```
private static final String NAME
```
    See Also:
    Constant Field Values
  - snapshot
```
private final org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.SnapshotDescription snapshot
```
  - monitor
```
private final ForeignExceptionDispatcher monitor
```
  - metricsSnapshot
```
private final MetricsSnapshot metricsSnapshot
```
  - status
```
private final MonitoredTask status
```
  - metaChanges
```
private RestoreSnapshotHelper.RestoreMetaChanges metaChanges
```
  - stopped
```
private volatile boolean stopped
```
- Constructor Detail
  - CloneSnapshotHandler
```
public CloneSnapshotHandler(MasterServices masterServices,
                    org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.SnapshotDescription snapshot,
                    HTableDescriptor hTableDescriptor)
```
- Method Detail
  - prepare
```
public CloneSnapshotHandler prepare()
                             throws NotAllMetaRegionsOnlineException,
                                    TableExistsException,
                                    IOException
```
    Description copied from class: EventHandler
    
    Event handlers should do all the necessary checks in this method (rather than in the constructor, or in process()) so that the caller, which is mostly executed in the ipc context can fail fast. Process is executed async from the client ipc, so this method gives a quick chance to do some basic checks. Should be called after constructing the EventHandler, and before process().
    
    Overrides:
    
    prepare in class CreateTableHandler
    
    Returns:
    the instance of this class
    
    Throws:
    
    NotAllMetaRegionsOnlineException
    
    TableExistsException
    
    IOException
  - handleCreateHdfsRegions
```
protected List<HRegionInfo> handleCreateHdfsRegions(org.apache.hadoop.fs.Path tableRootDir,
                                        TableName tableName)
                                             throws IOException
```
    Create the on-disk regions, using the tableRootDir provided by the CreateTableHandler. The cloned table will be created in a temp directory, and then the CreateTableHandler will be responsible to add the regions returned by this method to hbase:meta and do the assignment.
    
    Overrides:
    
    handleCreateHdfsRegions in class CreateTableHandler
    
    Parameters:
    tableRootDir - directory where the table is being created
    tableName - name of the table under construction
    
    Returns:
    the list of regions created
    
    Throws:
    
    IOException
  - addRegionsToMeta
```
protected void addRegionsToMeta(List<HRegionInfo> regionInfos,
                    int regionReplication)
                         throws IOException
```
    Description copied from class: CreateTableHandler
    
    Add the specified set of regions to the hbase:meta table.
    
    Overrides:
    
    addRegionsToMeta in class CreateTableHandler
    
    Throws:
    
    IOException
  - completed
```
protected void completed(Throwable exception)
```
    Description copied from class: CreateTableHandler
    
    Called after that process() is completed.
    
    Overrides:
    
    completed in class CreateTableHandler
    
    Parameters:
    exception - null if process() is successful or not null if something has failed.
  - isFinished
```
public boolean isFinished()
```
    Description copied from interface: SnapshotSentinel
    
    Check to see if the snapshot is finished, where finished may be success or failure.
    
    Specified by:
    
    isFinished in interface SnapshotSentinel
    
    Returns:
    false if the snapshot is still in progress, true if the snapshot has finished
  - getCompletionTimestamp
```
public long getCompletionTimestamp()
```
    Specified by:
    
    getCompletionTimestamp in interface SnapshotSentinel
    
    Returns:
    -1 if the snapshot is in progress, otherwise the completion timestamp.
  - getSnapshot
```
public org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.SnapshotDescription getSnapshot()
```
    Specified by:
    
    getSnapshot in interface SnapshotSentinel
    
    Returns:
    the description of the snapshot being run
  - cancel
```
public void cancel(String why)
```
    Description copied from interface: SnapshotSentinel
    
    Actively cancel a running snapshot.
    
    Specified by:
    
    cancel in interface SnapshotSentinel
    
    Parameters:
    why - Reason for cancellation.
  - getExceptionIfFailed
```
public ForeignException getExceptionIfFailed()
```
    Description copied from interface: SnapshotSentinel
    
    Get the exception that caused the snapshot to fail, if the snapshot has failed.
    
    Specified by:
    
    getExceptionIfFailed in interface SnapshotSentinel
    
    Returns:
    ForeignException that caused the snapshot to fail, or null if the snapshot is still in progress or has succeeded
  - rethrowExceptionIfFailed
```
public void rethrowExceptionIfFailed()
                              throws ForeignException
```
    Description copied from interface: SnapshotSentinel
    
    Rethrow the exception returned by SnapshotSentinel.getExceptionIfFailed(). If there is no exception this is a no-op.
    
    Specified by:
    
    rethrowExceptionIfFailed in interface SnapshotSentinel
    
    Throws:
    
    ForeignException - all exceptions from remote sources are procedure exceptions

Class CloneSnapshotHandler

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.hadoop.hbase.executor.EventHandler

Field Summary

Fields inherited from class org.apache.hadoop.hbase.master.handler.CreateTableHandler

Fields inherited from class org.apache.hadoop.hbase.executor.EventHandler

Constructor Summary

Method Summary

Methods inherited from class org.apache.hadoop.hbase.master.handler.CreateTableHandler

Methods inherited from class org.apache.hadoop.hbase.executor.EventHandler

Methods inherited from class java.lang.Object

Field Detail

LOG

NAME

snapshot

monitor

metricsSnapshot

status

metaChanges

stopped

Constructor Detail

CloneSnapshotHandler

Method Detail

prepare

handleCreateHdfsRegions

addRegionsToMeta

completed

isFinished

getCompletionTimestamp

getSnapshot

cancel

getExceptionIfFailed

rethrowExceptionIfFailed