final class LWWMap[A, B] extends DeltaReplicatedData with ReplicatedDataSerialization with RemovedNodePruning

Specialized ORMap with LWWRegister values.

LWWRegister relies on synchronized clocks and should only be used when the choice of value is not important for concurrent updates occurring within the clock skew.

Instead of using timestamps based on System.currentTimeMillis() time it is possible to use a timestamp value based on something else, for example an increasing version number from a database record that is used for optimistic concurrency control.

The defaultClock is using max value of System.currentTimeMillis() and currentTimestamp + 1. This means that the timestamp is increased for changes on the same node that occurs within the same millisecond. It also means that it is safe to use the LWWMap without synchronized clocks when there is only one active writer, e.g. a Cluster Singleton. Such a single writer should then first read current value with ReadMajority (or more) before changing and writing the value with WriteMajority (or more).

For first-write-wins semantics you can use the LWWRegister#reverseClock instead of the LWWRegister#defaultClock

This class is immutable, i.e. "modifying" methods return a new instance.

Annotations
@SerialVersionUID()
Source
LWWMap.scala
Linear Supertypes
RemovedNodePruning, ReplicatedDataSerialization, Serializable, DeltaReplicatedData, ReplicatedData, AnyRef, Any
Type Hierarchy
Ordering
  1. Alphabetic
  2. By Inheritance
Inherited
  1. LWWMap
  2. RemovedNodePruning
  3. ReplicatedDataSerialization
  4. Serializable
  5. DeltaReplicatedData
  6. ReplicatedData
  7. AnyRef
  8. Any
Implicitly
  1. by any2stringadd
  2. by StringFormat
  3. by Ensuring
  4. by ArrowAssoc
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Visibility
  1. Public
  2. Protected

Type Members

  1. type D = DeltaOp

    The type of the delta.

    The type of the delta. To be specified by subclass. It may be the same type as T or a different type if needed. For example GSet uses the same type and ORSet uses different types.

    Definition Classes
    LWWMap → DeltaReplicatedData
  2. type T = LWWMap[A, B]

    The type of the concrete implementation, e.g.

    The type of the concrete implementation, e.g. GSet[A]. To be specified by subclass.

    Definition Classes
    LWWMap → ReplicatedData

Value Members

  1. final def !=(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  2. final def ##: Int
    Definition Classes
    AnyRef → Any
  3. def +(other: String): String
    Implicit
    This member is added by an implicit conversion from LWWMap[A, B] toany2stringadd[LWWMap[A, B]] performed by method any2stringadd in scala.Predef.
    Definition Classes
    any2stringadd
  4. def ->[B](y: B): (LWWMap[A, B], B)
    Implicit
    This member is added by an implicit conversion from LWWMap[A, B] toArrowAssoc[LWWMap[A, B]] performed by method ArrowAssoc in scala.Predef.
    Definition Classes
    ArrowAssoc
    Annotations
    @inline()
  5. def :+(entry: (A, B))(implicit node: SelfUniqueAddress): LWWMap[A, B]

    Adds an entry to the map

  6. final def ==(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  7. final def asInstanceOf[T0]: T0
    Definition Classes
    Any
  8. def clone(): AnyRef
    Attributes
    protected[lang]
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.CloneNotSupportedException]) @HotSpotIntrinsicCandidate() @native()
  9. def contains(key: A): Boolean
  10. def delta: Option[D]

    The accumulated delta of mutator operations since previous #resetDelta.

    The accumulated delta of mutator operations since previous #resetDelta. When the Replicator invokes the modify function of the Update message and the user code is invoking one or more mutator operations the data is collecting the delta of the operations and makes it available for the Replicator with the #delta accessor. The modify function shall still return the full state in the same way as ReplicatedData without support for deltas.

    Definition Classes
    LWWMap → DeltaReplicatedData
  11. def ensuring(cond: (LWWMap[A, B]) => Boolean, msg: => Any): LWWMap[A, B]
    Implicit
    This member is added by an implicit conversion from LWWMap[A, B] toEnsuring[LWWMap[A, B]] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  12. def ensuring(cond: (LWWMap[A, B]) => Boolean): LWWMap[A, B]
    Implicit
    This member is added by an implicit conversion from LWWMap[A, B] toEnsuring[LWWMap[A, B]] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  13. def ensuring(cond: Boolean, msg: => Any): LWWMap[A, B]
    Implicit
    This member is added by an implicit conversion from LWWMap[A, B] toEnsuring[LWWMap[A, B]] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  14. def ensuring(cond: Boolean): LWWMap[A, B]
    Implicit
    This member is added by an implicit conversion from LWWMap[A, B] toEnsuring[LWWMap[A, B]] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  15. def entries: Map[A, B]

    Scala API: All entries of the map.

  16. final def eq(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  17. def equals(o: Any): Boolean
    Definition Classes
    LWWMap → AnyRef → Any
  18. def get(key: A): Option[B]
  19. final def getClass(): Class[_ <: AnyRef]
    Definition Classes
    AnyRef → Any
    Annotations
    @HotSpotIntrinsicCandidate() @native()
  20. def getEntries(): Map[A, B]

    Java API: All entries of the map.

  21. def hashCode(): Int
    Definition Classes
    LWWMap → AnyRef → Any
  22. def isEmpty: Boolean
  23. final def isInstanceOf[T0]: Boolean
    Definition Classes
    Any
  24. def merge(that: LWWMap[A, B]): LWWMap[A, B]

    Monotonic merge function.

    Monotonic merge function.

    Definition Classes
    LWWMap → ReplicatedData
  25. def mergeDelta(thatDelta: D): LWWMap[A, B]

    When delta is merged into the full state this method is used.

    When delta is merged into the full state this method is used. When the type D of the delta is of the same type as the full state T this method can be implemented by delegating to merge.

    Definition Classes
    LWWMap → DeltaReplicatedData
  26. def modifiedByNodes: Set[UniqueAddress]

    The nodes that have changed the state for this data and would need pruning when such node is no longer part of the cluster.

    The nodes that have changed the state for this data and would need pruning when such node is no longer part of the cluster.

    Definition Classes
    LWWMap → RemovedNodePruning
  27. final def ne(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  28. def needPruningFrom(removedNode: UniqueAddress): Boolean

    Does it have any state changes from a specific node, which has been removed from the cluster.

    Does it have any state changes from a specific node, which has been removed from the cluster.

    Definition Classes
    LWWMap → RemovedNodePruning
  29. final def notify(): Unit
    Definition Classes
    AnyRef
    Annotations
    @HotSpotIntrinsicCandidate() @native()
  30. final def notifyAll(): Unit
    Definition Classes
    AnyRef
    Annotations
    @HotSpotIntrinsicCandidate() @native()
  31. def prune(removedNode: UniqueAddress, collapseInto: UniqueAddress): LWWMap[A, B]

    When the removed node has been removed from the cluster the state changes from that node will be pruned by collapsing the data entries to another node.

    When the removed node has been removed from the cluster the state changes from that node will be pruned by collapsing the data entries to another node.

    Definition Classes
    LWWMap → RemovedNodePruning
  32. def pruningCleanup(removedNode: UniqueAddress): LWWMap[A, B]

    Remove data entries from a node that has been removed from the cluster and already been pruned.

    Remove data entries from a node that has been removed from the cluster and already been pruned.

    Definition Classes
    LWWMap → RemovedNodePruning
  33. def put(node: SelfUniqueAddress, key: A, value: B, clock: Clock[B]): LWWMap[A, B]

    Adds an entry to the map.

    Adds an entry to the map.

    You can provide your clock implementation instead of using timestamps based on System.currentTimeMillis() time. The timestamp can for example be an increasing version number from a database record that is used for optimistic concurrency control.

  34. def put(node: SelfUniqueAddress, key: A, value: B): LWWMap[A, B]

    Adds an entry to the map

  35. def remove(node: SelfUniqueAddress, key: A): LWWMap[A, B]

    Removes an entry from the map.

    Removes an entry from the map. Note that if there is a conflicting update on another node the entry will not be removed after merge.

  36. def resetDelta: LWWMap[A, B]

    Reset collection of deltas from mutator operations.

    Reset collection of deltas from mutator operations. When the Replicator invokes the modify function of the Update message the delta is always "reset" and when the user code is invoking one or more mutator operations the data is collecting the delta of the operations and makes it available for the Replicator with the #delta accessor. When the Replicator has grabbed the delta it will invoke this method to get a clean data instance without the delta.

    Definition Classes
    LWWMap → DeltaReplicatedData
  37. def size: Int
  38. final def synchronized[T0](arg0: => T0): T0
    Definition Classes
    AnyRef
  39. def toString(): String
    Definition Classes
    LWWMap → AnyRef → Any
  40. final def wait(arg0: Long, arg1: Int): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.InterruptedException])
  41. final def wait(arg0: Long): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.InterruptedException]) @native()
  42. final def wait(): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.InterruptedException])

Deprecated Value Members

  1. def finalize(): Unit
    Attributes
    protected[lang]
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.Throwable]) @Deprecated
    Deprecated

    (Since version 9)

  2. def formatted(fmtstr: String): String
    Implicit
    This member is added by an implicit conversion from LWWMap[A, B] toStringFormat[LWWMap[A, B]] performed by method StringFormat in scala.Predef.
    Definition Classes
    StringFormat
    Annotations
    @deprecated @inline()
    Deprecated

    (Since version 2.12.16) Use formatString.format(value) instead of value.formatted(formatString), or use the f"" string interpolator. In Java 15 and later, formatted resolves to the new method in String which has reversed parameters.

  3. def →[B](y: B): (LWWMap[A, B], B)
    Implicit
    This member is added by an implicit conversion from LWWMap[A, B] toArrowAssoc[LWWMap[A, B]] performed by method ArrowAssoc in scala.Predef.
    Definition Classes
    ArrowAssoc
    Annotations
    @deprecated
    Deprecated

    (Since version 2.13.0) Use -> instead. If you still wish to display it as one character, consider using a font with programming ligatures such as Fira Code.

Inherited from RemovedNodePruning

Inherited from ReplicatedDataSerialization

Inherited from Serializable

Inherited from DeltaReplicatedData

Inherited from ReplicatedData

Inherited from AnyRef

Inherited from Any

Inherited by implicit conversion any2stringadd fromLWWMap[A, B] to any2stringadd[LWWMap[A, B]]

Inherited by implicit conversion StringFormat fromLWWMap[A, B] to StringFormat[LWWMap[A, B]]

Inherited by implicit conversion Ensuring fromLWWMap[A, B] to Ensuring[LWWMap[A, B]]

Inherited by implicit conversion ArrowAssoc fromLWWMap[A, B] to ArrowAssoc[LWWMap[A, B]]

Ungrouped