alluxio.master.journal

Class JournaledGroup

java.lang.Object

alluxio.master.journal.JournaledGroup

All Implemented Interfaces:

Checkpointed, Journaled, JournalEntryIterable

public class JournaledGroup
extends Object
implements Journaled

Convenience class which groups together multiple Journaled components as a single Journaled component.

Field Summary

Fields inherited from interface alluxio.master.journal.checkpoint.Checkpointed

LOG

Constructor Summary

Constructors

Constructor and Description
JournaledGroup(List<Journaled> journaled, CheckpointName checkpointName) Creates an instance of a single journaled component, from a list of journaled components.

Method Summary

Modifier and Type	Method and Description
CheckpointName	getCheckpointName()
List<Journaled>	getJournaled()
CloseableIterator<Journal.JournalEntry>	getJournalEntryIterator()
boolean	processJournalEntry(Journal.JournalEntry entry) Attempts to apply a journal entry.
void	resetState() Resets the object's journaled state.
void	restoreFromCheckpoint(CheckpointInputStream input) Restores state from a checkpoint.
CompletableFuture<Void>	restoreFromCheckpoint(File directory, ExecutorService executorService) Restores state from a checkpoint asynchronously.
CompletableFuture<Void>	writeToCheckpoint(File directory, ExecutorService executorService) Writes a checkpoint to the specified directory asynchronously using the provided executor.
void	writeToCheckpoint(OutputStream output) Writes a checkpoint of all state to the given output stream.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface alluxio.master.journal.Journaled

applyAndJournal

Constructor Detail

JournaledGroup

public JournaledGroup(List<Journaled> journaled,
                      CheckpointName checkpointName)

Creates an instance of a single journaled component, from a list of journaled components.

Parameters:

journaled - the list of journaled components to be grouped

checkpointName - the name of the journal checkpoint for the group

Method Detail

getJournaled

public List<Journaled> getJournaled()

Returns:

the list of journaled components in this group

processJournalEntry

public boolean processJournalEntry(Journal.JournalEntry entry)

Description copied from interface: Journaled

Attempts to apply a journal entry.

Specified by:

processJournalEntry in interface Journaled

Parameters:

entry - the entry to apply

Returns:

whether the entry type is supported by this journaled object

resetState

public void resetState()

Description copied from interface: Journaled

Resets the object's journaled state.

Specified by:

resetState in interface Journaled

getCheckpointName

public CheckpointName getCheckpointName()

Specified by:

getCheckpointName in interface Checkpointed

Returns:

a name for this checkpointed class

writeToCheckpoint

public CompletableFuture<Void> writeToCheckpoint(File directory,
                                                 ExecutorService executorService)

Description copied from interface: Checkpointed

Writes a checkpoint to the specified directory asynchronously using the provided executor.

Specified by:

writeToCheckpoint in interface Checkpointed

Parameters:

directory - where the checkpoint will be written

executorService - to use when running tasks asynchronously

Returns:

a future that processes the computation

writeToCheckpoint

public void writeToCheckpoint(OutputStream output)
                       throws IOException,
                              InterruptedException

Description copied from interface: Checkpointed

Writes a checkpoint of all state to the given output stream. Implementations should make an effort to throw InterruptedException if they get interrupted while running.

Specified by:

writeToCheckpoint in interface Checkpointed

Specified by:

writeToCheckpoint in interface Journaled

Parameters:

output - the output stream to write to

Throws:

IOException

InterruptedException

restoreFromCheckpoint

public CompletableFuture<Void> restoreFromCheckpoint(File directory,
                                                     ExecutorService executorService)

Description copied from interface: Checkpointed

Restores state from a checkpoint asynchronously.

Specified by:

restoreFromCheckpoint in interface Checkpointed

Parameters:

directory - where the checkpoint will be located

executorService - to use when running asynchronous tasks

Returns:

a future to track the progress

restoreFromCheckpoint

public void restoreFromCheckpoint(CheckpointInputStream input)
                           throws IOException

Description copied from interface: Checkpointed

Restores state from a checkpoint.

Specified by:

restoreFromCheckpoint in interface Checkpointed

Specified by:

restoreFromCheckpoint in interface Journaled

Parameters:

input - an input stream with checkpoint data

Throws:

IOException

getJournalEntryIterator

public CloseableIterator<Journal.JournalEntry> getJournalEntryIterator()

Specified by:

getJournalEntryIterator in interface JournalEntryIterable

Returns:

an CloseableIterator that iterates all the journal entries