com.bigdata.ha

Interface QuorumCommit<S extends HACommitGlue>

All Known Subinterfaces:

QuorumService<S>

All Known Implementing Classes:

QuorumCommitImpl, QuorumServiceBase

public interface QuorumCommit<S extends HACommitGlue>

A non-remote interface for a member service in a Quorum defining methods to support service the 2-phase quorum commit protocol.

Version:

$Id$

Author:

Bryan Thompson

Method Summary

Methods

Modifier and Type	Method and Description
void	abort2Phase(long token) Used by the leader to send a message to each service joined with the quorum telling it to discard its write set, reloading all state from the last root block.
CommitResponse	commit2Phase(CommitRequest req) Used by the leader to send a message to each joined service in the quorum telling it to commit using the root block from the corresponding prepare message.
PrepareResponse	prepare2Phase(PrepareRequest req) Used by the leader to send a message to each joined service in the quorum instructing it to flush all writes to the backing channel, and acknowledge "yes" if ready to commit.

Method Detail

prepare2Phase

PrepareResponse prepare2Phase(PrepareRequest req)
                              throws InterruptedException,
                                     TimeoutException,
                                     IOException

Used by the leader to send a message to each joined service in the quorum instructing it to flush all writes to the backing channel, and acknowledge "yes" if ready to commit. If the service can not prepare for any reason, then it must return "no". The service must save a copy of the root block for use with the next commit message.

Returns:

The outcome of the distributed PREPARE request, indicating whether each service is prepared to commit.

Throws:

InterruptedException

TimeoutException

IOException

commit2Phase

CommitResponse commit2Phase(CommitRequest req)
                            throws IOException,
                                   InterruptedException

Used by the leader to send a message to each joined service in the quorum telling it to commit using the root block from the corresponding prepare message. The commit MAY NOT go forward unless both the current quorum token and the lastCommitTime on this message agree with the quorum token and lastCommitTime in the root block from the last "prepare" message.

Throws:

IOException

InterruptedException

abort2Phase

void abort2Phase(long token)
                 throws IOException,
                        InterruptedException

Used by the leader to send a message to each service joined with the quorum telling it to discard its write set, reloading all state from the last root block. If the node has not observed the corresponding "prepare" message then it should ignore this message.

Parameters:

token - The quorum token.

Throws:

IOException

InterruptedException