org.apache.hadoop.hdfs.qjournal.server

Class Journal

java.lang.Object

org.apache.hadoop.hdfs.qjournal.server.Journal

All Implemented Interfaces:

Closeable, AutoCloseable

public class Journal
extends Object
implements Closeable

A JournalNode can manage journals for several clusters at once. Each such journal is entirely independent despite being hosted by the same JVM.

Field Summary

Fields

Modifier and Type	Field and Description
static String	LAST_PROMISED_FILENAME
static String	LAST_WRITER_EPOCH

Method Summary

Methods

Modifier and Type	Method and Description
void	acceptRecovery(org.apache.hadoop.hdfs.qjournal.protocol.RequestInfo reqInfo, QJournalProtocolProtos.SegmentStateProto segment, URL fromUrl)
Boolean	canRollBack(org.apache.hadoop.hdfs.server.common.StorageInfo storage, org.apache.hadoop.hdfs.server.common.StorageInfo prevStorage, int targetLayoutVersion)
void	close() Unlock and release resources.
void	doFinalize()
void	doPreUpgrade()
void	doRollback()
void	doUpgrade(org.apache.hadoop.hdfs.server.common.StorageInfo sInfo)
void	finalizeLogSegment(org.apache.hadoop.hdfs.qjournal.protocol.RequestInfo reqInfo, long startTxId, long endTxId) Finalize the log segment at the given transaction ID.
RemoteEditLogManifest	getEditLogManifest(long sinceTxId, boolean inProgressOk)
Long	getJournalCTime()
long	getLastWriterEpoch()
void	heartbeat(org.apache.hadoop.hdfs.qjournal.protocol.RequestInfo reqInfo)
boolean	isFormatted()
QJournalProtocolProtos.PrepareRecoveryResponseProto	prepareRecovery(org.apache.hadoop.hdfs.qjournal.protocol.RequestInfo reqInfo, long segmentTxId)
void	purgeLogsOlderThan(org.apache.hadoop.hdfs.qjournal.protocol.RequestInfo reqInfo, long minTxIdToKeep)
void	startLogSegment(org.apache.hadoop.hdfs.qjournal.protocol.RequestInfo reqInfo, long txid, int layoutVersion) Start a new segment at the given txid.

Methods inherited from class java.lang.Object

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

Field Detail

LAST_PROMISED_FILENAME

public static final String LAST_PROMISED_FILENAME

See Also:

Constant Field Values

LAST_WRITER_EPOCH

public static final String LAST_WRITER_EPOCH

See Also:

Constant Field Values

Method Detail

close

public void close()
           throws IOException

Unlock and release resources.

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Throws:

IOException

getLastWriterEpoch

public long getLastWriterEpoch()
                        throws IOException

Throws:

IOException

heartbeat

public void heartbeat(org.apache.hadoop.hdfs.qjournal.protocol.RequestInfo reqInfo)
               throws IOException

Throws:

IOException

isFormatted

public boolean isFormatted()

startLogSegment

public void startLogSegment(org.apache.hadoop.hdfs.qjournal.protocol.RequestInfo reqInfo,
                   long txid,
                   int layoutVersion)
                     throws IOException

Start a new segment at the given txid. The previous segment must have already been finalized.

Throws:

IOException

finalizeLogSegment

public void finalizeLogSegment(org.apache.hadoop.hdfs.qjournal.protocol.RequestInfo reqInfo,
                      long startTxId,
                      long endTxId)
                        throws IOException

Finalize the log segment at the given transaction ID.

Throws:

IOException

purgeLogsOlderThan

public void purgeLogsOlderThan(org.apache.hadoop.hdfs.qjournal.protocol.RequestInfo reqInfo,
                      long minTxIdToKeep)
                        throws IOException

Throws:

IOException

See Also:

LogsPurgeable.purgeLogsOlderThan(long)

getEditLogManifest

public RemoteEditLogManifest getEditLogManifest(long sinceTxId,
                                       boolean inProgressOk)
                                         throws IOException

Throws:

IOException

See Also:

QJournalProtocol.getEditLogManifest(String, long, boolean)

prepareRecovery

public QJournalProtocolProtos.PrepareRecoveryResponseProto prepareRecovery(org.apache.hadoop.hdfs.qjournal.protocol.RequestInfo reqInfo,
                                                                  long segmentTxId)
                                                                    throws IOException

Throws:

IOException

See Also:

QJournalProtocol.prepareRecovery(RequestInfo, long)

acceptRecovery

public void acceptRecovery(org.apache.hadoop.hdfs.qjournal.protocol.RequestInfo reqInfo,
                  QJournalProtocolProtos.SegmentStateProto segment,
                  URL fromUrl)
                    throws IOException

Throws:

IOException

See Also:

QJournalProtocol.acceptRecovery(RequestInfo, QJournalProtocolProtos.SegmentStateProto, URL)

doPreUpgrade

public void doPreUpgrade()
                  throws IOException

Throws:

IOException

doUpgrade

public void doUpgrade(org.apache.hadoop.hdfs.server.common.StorageInfo sInfo)
               throws IOException

Throws:

IOException

doFinalize

public void doFinalize()
                throws IOException

Throws:

IOException

canRollBack

public Boolean canRollBack(org.apache.hadoop.hdfs.server.common.StorageInfo storage,
                  org.apache.hadoop.hdfs.server.common.StorageInfo prevStorage,
                  int targetLayoutVersion)
                    throws IOException

Throws:

IOException

doRollback

public void doRollback()
                throws IOException

Throws:

IOException

getJournalCTime

public Long getJournalCTime()
                     throws IOException

Throws:

IOException