Class GCounter

    • Constructor Detail

      • GCounter

        public GCounter​(scala.collection.immutable.Map<UniqueAddress,​scala.math.BigInt> state,
                        scala.Option<GCounter> delta)
    • Method Detail

      • $lessinit$greater$default$1

        public static scala.collection.immutable.Map<UniqueAddress,​scala.math.BigInt> $lessinit$greater$default$1()
        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.

        Returns:
        (undocumented)
      • $lessinit$greater$default$2

        public static scala.Option<GCounter> $lessinit$greater$default$2()
      • empty

        public static GCounter empty()
      • apply

        public static GCounter apply()
      • create

        public static GCounter create()
        Java API
        Returns:
        (undocumented)
      • unapply

        public static scala.Option<scala.math.BigInt> unapply​(GCounter c)
        Extract the value().
        Parameters:
        c - (undocumented)
        Returns:
        (undocumented)
      • state

        public scala.collection.immutable.Map<UniqueAddress,​scala.math.BigInt> state()
      • delta

        public scala.Option<GCounter> delta()
        Description copied from interface: DeltaReplicatedData
        The accumulated delta of mutator operations since previous DeltaReplicatedData.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 DeltaReplicatedData.delta() accessor. The modify function shall still return the full state in the same way as ReplicatedData without support for deltas.
        Specified by:
        delta in interface DeltaReplicatedData
        Returns:
        (undocumented)
      • value

        public scala.math.BigInt value()
        Scala API: Current total value of the counter.
        Returns:
        (undocumented)
      • getValue

        public java.math.BigInteger getValue()
        Java API: Current total value of the counter.
        Returns:
        (undocumented)
      • $colon$plus

        public GCounter $colon$plus​(long n,
                                    SelfUniqueAddress node)
        Increment the counter with the delta n specified. The delta must be zero or positive.
        Parameters:
        n - (undocumented)
        node - (undocumented)
        Returns:
        (undocumented)
      • $plus

        public GCounter $plus​(long n,
                              Cluster node)
        Deprecated.
        Use `:+` that takes a `SelfUniqueAddress` parameter instead. Since 2.5.20.
      • increment

        public GCounter increment​(SelfUniqueAddress node,
                                  long n)
        Increment the counter with the delta n specified. The delta n must be zero or positive.
        Parameters:
        node - (undocumented)
        n - (undocumented)
        Returns:
        (undocumented)
      • increment

        public GCounter increment​(Cluster node,
                                  long n)
        Deprecated.
        Use `increment` that takes a `SelfUniqueAddress` parameter instead. Since 2.5.20.
      • increment

        public GCounter increment​(UniqueAddress key)
        INTERNAL API
        Parameters:
        key - (undocumented)
        Returns:
        (undocumented)
      • increment

        public GCounter increment​(UniqueAddress key,
                                  scala.math.BigInt n)
        INTERNAL API
        Parameters:
        key - (undocumented)
        n - (undocumented)
        Returns:
        (undocumented)
      • increment$default$2

        public long increment$default$2()
      • merge

        public GCounter merge​(GCounter that)
        INTERNAL API
        Parameters:
        that - (undocumented)
        Returns:
        (undocumented)
      • resetDelta

        public GCounter resetDelta()
        Description copied from interface: DeltaReplicatedData
        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 DeltaReplicatedData.delta() accessor. When the Replicator has grabbed the delta it will invoke this method to get a clean data instance without the delta.
        Specified by:
        resetDelta in interface DeltaReplicatedData
        Returns:
        (undocumented)
      • needPruningFrom

        public boolean needPruningFrom​(UniqueAddress removedNode)
        Description copied from interface: RemovedNodePruning
        Does it have any state changes from a specific node, which has been removed from the cluster.
        Specified by:
        needPruningFrom in interface RemovedNodePruning
        Parameters:
        removedNode - (undocumented)
        Returns:
        (undocumented)
      • prune

        public GCounter prune​(UniqueAddress removedNode,
                              UniqueAddress collapseInto)
        Description copied from interface: RemovedNodePruning
        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.
        Specified by:
        prune in interface RemovedNodePruning
        Parameters:
        removedNode - (undocumented)
        collapseInto - (undocumented)
        Returns:
        (undocumented)
      • pruningCleanup

        public GCounter pruningCleanup​(UniqueAddress removedNode)
        Description copied from interface: RemovedNodePruning
        Remove data entries from a node that has been removed from the cluster and already been pruned.
        Specified by:
        pruningCleanup in interface RemovedNodePruning
        Parameters:
        removedNode - (undocumented)
        Returns:
        (undocumented)
      • toString

        public java.lang.String toString()
        Overrides:
        toString in class java.lang.Object
      • equals

        public boolean equals​(java.lang.Object o)
        Overrides:
        equals in class java.lang.Object
      • hashCode

        public int hashCode()
        Overrides:
        hashCode in class java.lang.Object