Interface MessageReplicator.Writer

All Superinterfaces:

AutoCloseable, Closeable, Replicator.Accessor, Replicator.Writer

Enclosing interface:

MessageReplicator

public static interface MessageReplicator.Writer
extends Replicator.Writer

Interface called by the group leader for proposing messages. When consensus has been reached, the messages are committed and become available for all members to read.

See Also:

• newWriter

Method Summary

Modifier and Type	Method	Description
default int	writeMessage(byte[] message)	Write a single message to the log.
default int	writeMessage(byte[] message, int offset, int length)	Write a single message to the log.
int	writeMessage(byte[] message, int offset, int length, boolean finished)	Write a single message to the log, as part of an atomic batch.

Methods inherited from interface Replicator.Accessor

addCommitListener, close, commitPosition, position, term, termEndPosition, termStartPosition, uponCommit, waitForCommit, waitForEndCommit

Modifier and Type	Method	Description
void	addCommitListener(LongConsumer listener)	Install a callback which receives a stream of commit position updates.
void	close()
long	commitPosition()	Returns the current term commit position, which might be lower than the start position.
long	position()	Returns the next log position which will be accessed.
long	term()	Returns the fixed term being accessed.
long	termEndPosition()	Returns the current term end position, which is Long.MAX_VALUE if unbounded.
long	termStartPosition()	Returns the position at the start of the term.
void	uponCommit(long position, LongConsumer task)	Invokes the given task when the commit position reaches the requested position.
long	waitForCommit(long position, long nanosTimeout)	Blocks until the commit position reaches the given position.
default long	waitForEndCommit(long nanosTimeout)	Blocks until the commit position reaches the end of the term.

Method Details

writeMessage

default int writeMessage(byte[] message)
                  throws IOException

Write a single message to the log. Equivalent to: writeMessage(message, 0, message.length, true)

Returns:

1 if successful, -1 if fully deactivated, or 0 if should write any remaining messages and then close the writer

Throws:

IOException

writeMessage

default int writeMessage(byte[] message,
 int offset,
 int length)
                  throws IOException

Write a single message to the log. Equivalent to: writeMessage(message, offset, length, true)

Returns:

1 if successful, -1 if fully deactivated, or 0 if should write any remaining messages and then close the writer

Throws:

IOException

writeMessage

int writeMessage(byte[] message,
 int offset,
 int length,
 boolean finished)
          throws IOException

Write a single message to the log, as part of an atomic batch. When read back, all messages in the batch are still separate from each other. Pass false to the finished parameter for all messages in the batch except the last one. To work correctly, no other threads should be granted access to the writer in the middle of a batch.

Parameters:

finished - pass true for the last message in the batch

Returns:

1 if successful, -1 if fully deactivated, or 0 if should write any remaining messages and then close the writer

Throws:

IOException