LWWRegister

A delta-based CRDT Last Writer Wins (LWW) register.

Only the last written value is retained: the previous value (if any) is discarded.

When merging, only the value associated with the greatest timestamp is retained. A deletion is represented as a null value and handled the same way.

Its JSON serialization respects the following schema:

{
  "type": "LWWRegister",
  "metadata": Timestamp.toJson(),
  "value": $value
}

Constructors

LWWRegister

common

fun LWWRegister()

Constructs an empty LWWRegister instance.

LWWRegister

common

fun LWWRegister(env: Environment)

LWWRegister

common

fun LWWRegister(value: String, env: Environment)

Constructs a LWWRegister instance initialized with a given value and environment.

LWWRegister

common

fun LWWRegister(other: LWWRegister)

Copy constructor, discarding associated environment

Types

Companion

common

object Companion

Functions

assign

common

fun assign(v: String): LWWRegister

Assigns a given value to the register.

equals

common

open operator fun equals(other: Any?): Boolean

generateDelta

common

open override fun generateDelta(vv: VersionVector): LWWRegister

Return a delta from a given version vector vv to current state.

get

common

fun get(): String?

Gets the value currently stored in the register.

hashCode

common

open fun hashCode(): Int

merge

common

open override fun merge(delta: DeltaCRDT)

Merge a given delta into this DeltaCRDTThe merge is unidirectional: only the local replica is modified.

toJson

common

open override fun toJson(): String

Serialize this DeltaCRDT to a JSON string.

toString

common

open fun toString(): String

Properties

common

var ts: Timestamp? = null

The timestamp associated to the value.

value

common

var value: String? = null

The string value stored in the register.