org.apache.zookeeper.server.persistence

Interface TxnLog

All Known Implementing Classes:

FileTxnLog

public interface TxnLog

Interface for reading transaction logs.

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static interface	TxnLog.TxnIterator an iterating interface for reading transaction logs.

Method Summary

Modifier and Type	Method and Description
boolean	append(TxnHeader hdr, Record r) Append a request to the transaction log
void	close() close the transactions logs
void	commit() commit the transaction and make sure they are persisted
long	getDbId() the dbid for this transaction log.
long	getLastLoggedZxid() the last zxid of the logged transactions.
long	getTxnLogSyncElapsedTime()
TxnLog.TxnIterator	read(long zxid) Start reading the transaction logs from a given zxid
void	rollLog() roll the current log being appended to
void	setServerStats(ServerStats serverStats) Setter for ServerStats to monitor fsync threshold exceed
boolean	truncate(long zxid) truncate the log to get in sync with the leader.

Method Detail

setServerStats

void setServerStats(ServerStats serverStats)

Setter for ServerStats to monitor fsync threshold exceed

Parameters:

serverStats - used to update fsyncThresholdExceedCount

rollLog

void rollLog()
      throws IOException

roll the current log being appended to

Throws:

IOException

append

boolean append(TxnHeader hdr,
               Record r)
        throws IOException

Append a request to the transaction log

Parameters:

hdr - the transaction header

r - the transaction itself returns true iff something appended, otw false

Throws:

IOException

read

TxnLog.TxnIterator read(long zxid)
                 throws IOException

Start reading the transaction logs from a given zxid

Parameters:

zxid -

Returns:

returns an iterator to read the next transaction in the logs.

Throws:

IOException

getLastLoggedZxid

long getLastLoggedZxid()
                throws IOException

the last zxid of the logged transactions.

Returns:

the last zxid of the logged transactions.

Throws:

IOException

truncate

boolean truncate(long zxid)
          throws IOException

truncate the log to get in sync with the leader.

Parameters:

zxid - the zxid to truncate at.

Throws:

IOException

getDbId

long getDbId()
      throws IOException

the dbid for this transaction log.

Returns:

the dbid for this transaction log.

Throws:

IOException

commit

void commit()
     throws IOException

commit the transaction and make sure they are persisted

Throws:

IOException

getTxnLogSyncElapsedTime

long getTxnLogSyncElapsedTime()

Returns:

transaction log's elapsed sync time in milliseconds

close

void close()
    throws IOException

close the transactions logs

Throws:

IOException