final class GCounter extends DeltaReplicatedData with ReplicatedDelta with ReplicatedDataSerialization with RemovedNodePruning with FastMerge
Implements a 'Growing Counter' CRDT, also called a 'G-Counter'.
It is described in the paper A comprehensive study of Convergent and Commutative Replicated Data Types.
A G-Counter is a increment-only counter (inspired by vector clocks) in which only increment and merge are possible. Incrementing the counter adds 1 to the count for the current node. Divergent histories are resolved by taking the maximum count for each node (like a vector clock merge). The value of the counter is the sum of all node counts.
This class is immutable, i.e. "modifying" methods return a new instance.
- Annotations
- @SerialVersionUID()
- Source
- GCounter.scala
- Alphabetic
- By Inheritance
- GCounter
- FastMerge
- RemovedNodePruning
- ReplicatedDataSerialization
- Serializable
- ReplicatedDelta
- DeltaReplicatedData
- ReplicatedData
- AnyRef
- Any
- by any2stringadd
- by StringFormat
- by Ensuring
- by ArrowAssoc
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- Public
- Protected
Type Members
- type D = GCounter
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 exampleGSet
uses the same type andORSet
uses different types.- Definition Classes
- GCounter → DeltaReplicatedData
- type T = GCounter
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
- GCounter → ReplicatedData
Value Members
- final def !=(arg0: Any): Boolean
- Definition Classes
- AnyRef → Any
- final def ##: Int
- Definition Classes
- AnyRef → Any
- def +(other: String): String
- def ->[B](y: B): (GCounter, B)
- def :+(n: Long)(implicit node: SelfUniqueAddress): GCounter
Increment the counter with the delta
n
specified.Increment the counter with the delta
n
specified. The delta must be zero or positive. - final def ==(arg0: Any): Boolean
- Definition Classes
- AnyRef → Any
- final def asInstanceOf[T0]: T0
- Definition Classes
- Any
- def clone(): AnyRef
- Attributes
- protected[lang]
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.CloneNotSupportedException]) @HotSpotIntrinsicCandidate() @native()
- val delta: Option[GCounter]
The accumulated delta of mutator operations since previous #resetDelta.
The accumulated delta of mutator operations since previous #resetDelta. When the
Replicator
invokes themodify
function of theUpdate
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 theReplicator
with the #delta accessor. Themodify
function shall still return the full state in the same way asReplicatedData
without support for deltas.- Definition Classes
- GCounter → DeltaReplicatedData
- def ensuring(cond: (GCounter) => Boolean, msg: => Any): GCounter
- def ensuring(cond: (GCounter) => Boolean): GCounter
- def ensuring(cond: Boolean, msg: => Any): GCounter
- def ensuring(cond: Boolean): GCounter
- final def eq(arg0: AnyRef): Boolean
- Definition Classes
- AnyRef
- def equals(o: Any): Boolean
- Definition Classes
- GCounter → AnyRef → Any
- final def getClass(): Class[_ <: AnyRef]
- Definition Classes
- AnyRef → Any
- Annotations
- @HotSpotIntrinsicCandidate() @native()
- def getValue: BigInteger
Java API: Current total value of the counter.
- def hashCode(): Int
- Definition Classes
- GCounter → AnyRef → Any
- def increment(node: SelfUniqueAddress, n: Long): GCounter
Increment the counter with the delta
n
specified.Increment the counter with the delta
n
specified. The deltan
must be zero or positive. - final def isInstanceOf[T0]: Boolean
- Definition Classes
- Any
- def merge(that: GCounter): GCounter
Monotonic merge function.
Monotonic merge function.
- Definition Classes
- GCounter → ReplicatedData
- def mergeDelta(thatDelta: GCounter): GCounter
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 stateT
this method can be implemented by delegating tomerge
.- Definition Classes
- GCounter → DeltaReplicatedData
- 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
- GCounter → RemovedNodePruning
- final def ne(arg0: AnyRef): Boolean
- Definition Classes
- AnyRef
- 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
- GCounter → RemovedNodePruning
- final def notify(): Unit
- Definition Classes
- AnyRef
- Annotations
- @HotSpotIntrinsicCandidate() @native()
- final def notifyAll(): Unit
- Definition Classes
- AnyRef
- Annotations
- @HotSpotIntrinsicCandidate() @native()
- def prune(removedNode: UniqueAddress, collapseInto: UniqueAddress): GCounter
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
- GCounter → RemovedNodePruning
- def pruningCleanup(removedNode: UniqueAddress): GCounter
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
- GCounter → RemovedNodePruning
- def resetDelta: GCounter
Reset collection of deltas from mutator operations.
Reset collection of deltas from mutator operations. When the
Replicator
invokes themodify
function of theUpdate
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 theReplicator
with the #delta accessor. When theReplicator
has grabbed thedelta
it will invoke this method to get a clean data instance without the delta.- Definition Classes
- GCounter → DeltaReplicatedData
- final def synchronized[T0](arg0: => T0): T0
- Definition Classes
- AnyRef
- def toString(): String
- Definition Classes
- GCounter → AnyRef → Any
- def value: BigInt
Scala API: Current total value of the counter.
- final def wait(arg0: Long, arg1: Int): Unit
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.InterruptedException])
- final def wait(arg0: Long): Unit
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.InterruptedException]) @native()
- final def wait(): Unit
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.InterruptedException])
- def zero: GCounter
The empty full state.
The empty full state. This is used when a delta is received and no existing full state exists on the receiving side. Then the delta is merged into the
zero
to create the initial full state.- Definition Classes
- GCounter → ReplicatedDelta
Deprecated Value Members
- def finalize(): Unit
- Attributes
- protected[lang]
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.Throwable]) @Deprecated
- Deprecated
(Since version 9)
- def formatted(fmtstr: String): String
- Implicit
- This member is added by an implicit conversion from GCounter toStringFormat[GCounter] performed by method StringFormat in scala.Predef.
- Definition Classes
- StringFormat
- Annotations
- @deprecated @inline()
- Deprecated
(Since version 2.12.16) Use
formatString.format(value)
instead ofvalue.formatted(formatString)
, or use thef""
string interpolator. In Java 15 and later,formatted
resolves to the new method in String which has reversed parameters.
- def →[B](y: B): (GCounter, B)
- Implicit
- This member is added by an implicit conversion from GCounter toArrowAssoc[GCounter] 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.