Enum Class RaftState

java.lang.Object

java.lang.Enum<RaftState>

com.loomcache.server.consensus.RaftState

All Implemented Interfaces:

Serializable, Comparable<RaftState>, Constable

public enum RaftState
extends Enum<RaftState>

The possible states a Raft node can be in.

Transitions:

• LEARNER ──(promoted via config change)──> FOLLOWER
• FOLLOWER ──(election timeout)──> CANDIDATE
• CANDIDATE ──(wins majority)──> LEADER
• CANDIDATE ──(discovers higher term)──> FOLLOWER
• LEADER ──(discovers higher term)──> FOLLOWER

Learners receive log replication from the leader but do NOT:

• Participate in elections (cannot become CANDIDATE)
• Count toward quorum decisions (commitIndex advancement)

Learners are used for:

• Safe cluster scaling (add learner first, then promote to voter)
• Read replicas (serve stale reads from learners)
• Observation nodes (monitoring without affecting consensus)

Since:

1.0

See Also:

• RaftNode

Nested Class Summary

Nested classes/interfaces inherited from class Enum

Enum.EnumDesc<E>

Enum Constant Summary

Enum Constants

Enum Constant	Description
CANDIDATE
FOLLOWER
LEADER
LEARNER

Method Summary

Modifier and Type	Method	Description
static RaftState	valueOf(String name)	Returns the enum constant of this class with the specified name.
static RaftState[]	values()	Returns an array containing the constants of this enum class, in the order they are declared.

Methods inherited from class Enum

clone, compareTo, describeConstable, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods inherited from class Object

getClass, notify, notifyAll, wait, wait, wait

Enum Constant Details

LEARNER

public static final RaftState LEARNER

FOLLOWER

public static final RaftState FOLLOWER

CANDIDATE

public static final RaftState CANDIDATE

LEADER

public static final RaftState LEADER

Method Details

values

public static RaftState[] values()

Returns an array containing the constants of this enum class, in the order they are declared.

Returns:

an array containing the constants of this enum class, in the order they are declared

valueOf

public static RaftState valueOf(String name)

Returns the enum constant of this class with the specified name. The string must match exactly an identifier used to declare an enum constant in this class. (Extraneous whitespace characters are not permitted.)

Parameters:

name - the name of the enum constant to be returned.

Returns:

the enum constant with the specified name

Throws:

IllegalArgumentException - if this enum class has no constant with the specified name

NullPointerException - if the argument is null