org.apache.tephra.persist

Class AbstractTransactionLog

java.lang.Object

org.apache.tephra.persist.AbstractTransactionLog

All Implemented Interfaces:

TransactionLog

Direct Known Subclasses:

HDFSTransactionLog, LocalFileTransactionLog

public abstract class AbstractTransactionLog
extends Object
implements TransactionLog

Common implementation of a transaction log, backed by file reader and writer based storage. Classes extending this class, must also implement TransactionLogWriter and TransactionLogReader.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	AbstractTransactionLog.Entry Represents an entry in the transaction log.

Field Summary

Fields

Modifier and Type	Field and Description
protected long	timestamp

Constructor Summary

Constructors

Constructor and Description
AbstractTransactionLog(long timestamp, MetricsCollector metricsCollector)

Method Summary

Methods

Modifier and Type	Method and Description
void	append(List<TransactionEdit> edits)
void	append(TransactionEdit edit)
void	close()
protected abstract TransactionLogWriter	createWriter() Returns a log writer to be used for appending any new TransactionEdit objects.
abstract String	getName()
abstract TransactionLogReader	getReader()
long	getTimestamp()
void	init() Initializes the log file, opening a file writer.
boolean	isClosed()

Methods inherited from class java.lang.Object

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

Field Detail

timestamp

protected long timestamp

Constructor Detail

AbstractTransactionLog

public AbstractTransactionLog(long timestamp,
                      MetricsCollector metricsCollector)

Method Detail

init

public void init()
          throws IOException

Initializes the log file, opening a file writer. Clients calling init() should ensure that they also call close().

Throws:

IOException - If an error is encountered initializing the file writer.

createWriter

protected abstract TransactionLogWriter createWriter()
                                              throws IOException

Returns a log writer to be used for appending any new TransactionEdit objects.

Throws:

IOException

getName

public abstract String getName()

Specified by:

getName in interface TransactionLog

getTimestamp

public long getTimestamp()

Specified by:

getTimestamp in interface TransactionLog

append

public void append(TransactionEdit edit)
            throws IOException

Specified by:

append in interface TransactionLog

Throws:

IOException

append

public void append(List<TransactionEdit> edits)
            throws IOException

Specified by:

append in interface TransactionLog

Throws:

IOException

close

public void close()
           throws IOException

Specified by:

close in interface TransactionLog

Throws:

IOException

isClosed

public boolean isClosed()

getReader

public abstract TransactionLogReader getReader()
                                        throws IOException

Specified by:

getReader in interface TransactionLog

Throws:

IOException