Package org.opendaylight.controller.cluster.raft.behaviors

Class AbstractRaftActorBehavior

java.lang.Object

org.opendaylight.controller.cluster.raft.behaviors.AbstractRaftActorBehavior

All Implemented Interfaces:

AutoCloseable, RaftActorBehavior

Direct Known Subclasses:

AbstractLeader, Candidate, Follower

public abstract class AbstractRaftActorBehavior
extends Object
implements RaftActorBehavior

Abstract class that provides common code for a RaftActor behavior.

Field Summary

Fields

Modifier and Type	Field	Description
protected RaftActorContext	context	Information about the RaftActor whose behavior this class represents.
protected Logger	log	Used for message logging.

Method Summary

Modifier and Type	Method	Description
protected ActorRef	actor()	Returns the actor associated with this behavior.
protected RaftActorBehavior	appendEntries(ActorRef sender, AppendEntries appendEntries)	Handles the common logic for the AppendEntries message and delegates handling to the derived class.
protected void	applyLogToStateMachine(long index)	Applies the log entries up to the specified index that is known to be committed to the state machine.
protected boolean	canGrantVote(RequestVote requestVote)
protected boolean	canStartElection()
static RaftActorBehavior	createBehavior(RaftActorContext context, RaftState state)
protected long	currentTerm()	Returns the current election term.
protected scala.concurrent.duration.FiniteDuration	electionDuration()	Returns a duration for election with an additional variance for randomness.
protected String	getId()
protected long	getLogEntryIndex(long index)	Returns the actual index of the entry in replicated log for the given index or -1 if not found.
protected long	getLogEntryOrSnapshotTerm(long index)	Returns the actual term of the entry in the replicated log for the given index or, if not present, returns the snapshot term if the given index is in the snapshot or -1 otherwise.
protected long	getLogEntryTerm(long index)	Returns the actual term of the entry in the replicated log for the given index or -1 if not found.
protected int	getMajorityVoteCount(int numPeers)
long	getReplicatedToAllIndex()	Returns the index of the last log entry that has been replicated to all peers.
protected abstract RaftActorBehavior	handleAppendEntries(ActorRef sender, AppendEntries appendEntries)	Derived classes should not directly handle AppendEntries messages it should let the base class handle it first.
protected abstract RaftActorBehavior	handleAppendEntriesReply(ActorRef sender, AppendEntriesReply appendEntriesReply)	Derived classes should not directly handle AppendEntriesReply messages it should let the base class handle it first.
RaftActorBehavior	handleMessage(ActorRef sender, Object message)	Handle a message.
protected abstract RaftActorBehavior	handleRequestVoteReply(ActorRef sender, RequestVoteReply requestVoteReply)	Derived classes should not directly handle RequestVoteReply messages it should let the base class handle it first.
protected RaftActorBehavior	internalSwitchBehavior(RaftActorBehavior newBehavior)
protected RaftActorBehavior	internalSwitchBehavior(RaftState newState)
protected long	lastIndex()	Returns the index of the last entry in the log.
protected long	lastTerm()	Returns the term of the last entry in the log.
protected String	logName()
protected void	performSnapshotWithoutCapture(long snapshotCapturedIndex)	Performs a snapshot with no capture on the replicated log.
protected RaftActorBehavior	requestVote(ActorRef sender, RequestVote requestVote)	Handles the logic for the RequestVote message that is common for all behaviors.
protected void	scheduleElection(scala.concurrent.duration.FiniteDuration interval)	Schedule a new election.
void	setReplicatedToAllIndex(long replicatedToAllIndex)	Sets the index of the last log entry that has been replicated to all peers.
protected boolean	shouldUpdateTerm(RaftRPC rpc)
RaftState	state()	Returns the state associated with this behavior.
protected void	stopElection()	Stops the currently scheduled election.
RaftActorBehavior	switchBehavior(RaftActorBehavior behavior)	Closes the current behavior and switches to the specified behavior, if possible.
protected String	votedFor()	Returns the id of the candidate that this server voted for in current term.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.opendaylight.controller.cluster.raft.behaviors.RaftActorBehavior

close, getLeaderId, getLeaderPayloadVersion

Field Detail

context

protected final RaftActorContext context

Information about the RaftActor whose behavior this class represents.

log

protected final Logger log

Used for message logging.

Method Detail

createBehavior

public static RaftActorBehavior createBehavior(RaftActorContext context,
                                               RaftState state)

state

public final RaftState state()

Description copied from interface: RaftActorBehavior

Returns the state associated with this behavior.

Specified by:

state in interface RaftActorBehavior

Returns:

the RaftState

logName

protected final String logName()

setReplicatedToAllIndex

public void setReplicatedToAllIndex(long replicatedToAllIndex)

Description copied from interface: RaftActorBehavior

Sets the index of the last log entry that has been replicated to all peers.

Specified by:

setReplicatedToAllIndex in interface RaftActorBehavior

Parameters:

replicatedToAllIndex - the index

getReplicatedToAllIndex

public long getReplicatedToAllIndex()

Description copied from interface: RaftActorBehavior

Returns the index of the last log entry that has been replicated to all peers.

Specified by:

getReplicatedToAllIndex in interface RaftActorBehavior

Returns:

the index or -1 if not known

handleAppendEntries

protected abstract RaftActorBehavior handleAppendEntries(ActorRef sender,
                                                         AppendEntries appendEntries)

Derived classes should not directly handle AppendEntries messages it should let the base class handle it first. Once the base class handles the AppendEntries message and does the common actions that are applicable in all RaftState's it will delegate the handling of the AppendEntries message to the derived class to do more state specific handling by calling this method

Parameters:

sender - The actor that sent this message

appendEntries - The AppendEntries message

Returns:

a new behavior if it was changed or the current behavior

appendEntries

protected RaftActorBehavior appendEntries(ActorRef sender,
                                          AppendEntries appendEntries)

Handles the common logic for the AppendEntries message and delegates handling to the derived class.

Parameters:

sender - the ActorRef that sent the message

appendEntries - the message

Returns:

a new behavior if it was changed or the current behavior

handleAppendEntriesReply

protected abstract RaftActorBehavior handleAppendEntriesReply(ActorRef sender,
                                                              AppendEntriesReply appendEntriesReply)

Derived classes should not directly handle AppendEntriesReply messages it should let the base class handle it first. Once the base class handles the AppendEntriesReply message and does the common actions that are applicable in all RaftState's it will delegate the handling of the AppendEntriesReply message to the derived class to do more state specific handling by calling this method

Parameters:

sender - The actor that sent this message

appendEntriesReply - The AppendEntriesReply message

Returns:

a new behavior if it was changed or the current behavior

requestVote

protected RaftActorBehavior requestVote(ActorRef sender,
                                        RequestVote requestVote)

Handles the logic for the RequestVote message that is common for all behaviors.

Parameters:

sender - the ActorRef that sent the message

requestVote - the message

Returns:

a new behavior if it was changed or the current behavior

canGrantVote

protected boolean canGrantVote(RequestVote requestVote)

handleRequestVoteReply

protected abstract RaftActorBehavior handleRequestVoteReply(ActorRef sender,
                                                            RequestVoteReply requestVoteReply)

Derived classes should not directly handle RequestVoteReply messages it should let the base class handle it first. Once the base class handles the RequestVoteReply message and does the common actions that are applicable in all RaftState's it will delegate the handling of the RequestVoteReply message to the derived class to do more state specific handling by calling this method

Parameters:

sender - The actor that sent this message

requestVoteReply - The RequestVoteReply message

Returns:

a new behavior if it was changed or the current behavior

electionDuration

protected scala.concurrent.duration.FiniteDuration electionDuration()

Returns a duration for election with an additional variance for randomness.

Returns:

a random election duration

stopElection

protected void stopElection()

Stops the currently scheduled election.

canStartElection

protected boolean canStartElection()

scheduleElection

protected void scheduleElection(scala.concurrent.duration.FiniteDuration interval)

Schedule a new election.

Parameters:

interval - the duration after which we should trigger a new election

currentTerm

protected long currentTerm()

Returns the current election term.

Returns:

the current term

votedFor

protected String votedFor()

Returns the id of the candidate that this server voted for in current term.

Returns:

the candidate for whom we voted in the current term

actor

protected ActorRef actor()

Returns the actor associated with this behavior.

Returns:

the actor

lastTerm

protected long lastTerm()

Returns the term of the last entry in the log.

Returns:

the term

lastIndex

protected long lastIndex()

Returns the index of the last entry in the log.

Returns:

the index

getLogEntryIndex

protected long getLogEntryIndex(long index)

Returns the actual index of the entry in replicated log for the given index or -1 if not found.

Returns:

the log entry index or -1 if not found

getLogEntryTerm

protected long getLogEntryTerm(long index)

Returns the actual term of the entry in the replicated log for the given index or -1 if not found.

Returns:

the log entry term or -1 if not found

getLogEntryOrSnapshotTerm

protected long getLogEntryOrSnapshotTerm(long index)

Returns the actual term of the entry in the replicated log for the given index or, if not present, returns the snapshot term if the given index is in the snapshot or -1 otherwise.

Returns:

the term or -1 otherwise

applyLogToStateMachine

protected void applyLogToStateMachine(long index)

Applies the log entries up to the specified index that is known to be committed to the state machine.

Parameters:

index - the log index

handleMessage

public RaftActorBehavior handleMessage(ActorRef sender,
                                       Object message)

Description copied from interface: RaftActorBehavior

Handle a message. If the processing of the message warrants a state change then a new behavior should be returned otherwise this method should return the current behavior.

Specified by:

handleMessage in interface RaftActorBehavior

Parameters:

sender - The sender of the message

message - A message that needs to be processed

Returns:

The new behavior or current behavior, or null if the message was not handled.

switchBehavior

public RaftActorBehavior switchBehavior(RaftActorBehavior behavior)

Description copied from interface: RaftActorBehavior

Closes the current behavior and switches to the specified behavior, if possible.

Specified by:

switchBehavior in interface RaftActorBehavior

Parameters:

behavior - the new behavior to switch to

Returns:

the new behavior

internalSwitchBehavior

protected RaftActorBehavior internalSwitchBehavior(RaftState newState)

internalSwitchBehavior

protected RaftActorBehavior internalSwitchBehavior(RaftActorBehavior newBehavior)

getMajorityVoteCount

protected int getMajorityVoteCount(int numPeers)

performSnapshotWithoutCapture

protected void performSnapshotWithoutCapture(long snapshotCapturedIndex)

Performs a snapshot with no capture on the replicated log. It clears the log from the supplied index or lastApplied-1 which ever is minimum.

Parameters:

snapshotCapturedIndex - the index from which to clear

getId

protected String getId()

shouldUpdateTerm

protected boolean shouldUpdateTerm(RaftRPC rpc)