Package org.infinispan.distribution.ch.impl

Class ReplicatedConsistentHash

java.lang.Object
org.infinispan.distribution.ch.impl.ReplicatedConsistentHash
All Implemented Interfaces:
ConsistentHash
public class ReplicatedConsistentHash extends Object implements ConsistentHash
Special implementation of ConsistentHash for replicated caches. The hash-space has several segments owned by all members and the primary ownership of each segment is evenly spread between members.
Since:
5.2
Author:
Dan Berindei, anistor@redhat.com

  • Constructor Details

    • ReplicatedConsistentHash

      public ReplicatedConsistentHash(List<Address> members, int[] primaryOwners)

    • ReplicatedConsistentHash

      public ReplicatedConsistentHash(List<Address> members, Map<Address,Float> capacityFactors, List<Address> membersWithoutState, int[] primaryOwners)

  • Method Details

    • union

      public ReplicatedConsistentHash union(ReplicatedConsistentHash ch2)

    • getNumSegments

      public int getNumSegments()
      Specified by:
      getNumSegments in interface ConsistentHash
      Returns:
      The actual number of hash space segments. Note that it may not be the same as the number of segments passed in at creation time.

    • getNumOwners

      public int getNumOwners()

    • getMembers

      public List<Address> getMembers()
      Description copied from interface: ConsistentHash
      Should return the addresses of the nodes used to create this consistent hash.
      Specified by:
      getMembers in interface ConsistentHash
      Returns:
      set of node addresses.

    • locateOwnersForSegment

      public List<Address> locateOwnersForSegment(int segmentId)
      Specified by:
      locateOwnersForSegment in interface ConsistentHash
      Returns:
      All the nodes that own a given hash space segment, first address is the primary owner. The returned list is unmodifiable.

    • locatePrimaryOwnerForSegment

      public Address locatePrimaryOwnerForSegment(int segmentId)
      Specified by:
      locatePrimaryOwnerForSegment in interface ConsistentHash
      Returns:
      The primary owner of a given hash space segment. This is equivalent to locateOwnersForSegment(segmentId).get(0) but is more efficient

    • getSegmentsForOwner

      public Set<Integer> getSegmentsForOwner(Address owner)
      Description copied from interface: ConsistentHash
      Returns the segments owned by a cache member.
      Specified by:
      getSegmentsForOwner in interface ConsistentHash
      Parameters:
      owner - the address of the member
      Returns:
      a non-null set of segment IDs, may or may not be unmodifiable, which shouldn't be modified by caller. The set is empty if owner is not a member of the consistent hash.

    • getPrimarySegmentsForOwner

      public Set<Integer> getPrimarySegmentsForOwner(Address owner)
      Description copied from interface: ConsistentHash
      Returns the segments that this cache member is the primary owner for.
      Specified by:
      getPrimarySegmentsForOwner in interface ConsistentHash
      Parameters:
      owner - the address of the member
      Returns:
      a non-null set of segment IDs, may or may not be unmodifiable, which shouldn't be modified by caller. The set is empty if owner is not a member of the consistent hash.

    • getRoutingTableAsString

      public String getRoutingTableAsString()
      Description copied from interface: ConsistentHash
      Returns a string containing all the segments and their associated addresses.
      Specified by:
      getRoutingTableAsString in interface ConsistentHash

    • isSegmentLocalToNode

      public boolean isSegmentLocalToNode(Address nodeAddress, int segmentId)
      Description copied from interface: ConsistentHash
      Check if a segment is local to a given member.

      Implementation note: normally key-based method are implemented based on segment-based methods. Here, however, we need a default implementation for the segment-based method for backwards-compatibility reasons.

      Specified by:
      isSegmentLocalToNode in interface ConsistentHash

    • isReplicated

      public boolean isReplicated()
      Specified by:
      isReplicated in interface ConsistentHash
      Returns:
      true if every member owns every segment. This allows callers to skip computing the segment of a key in some cases.

    • toScopedState

      public void toScopedState(ScopedPersistentState state)
      Description copied from interface: ConsistentHash
      Writes this ConsistentHash to the specified scoped state. Before invoking this method, the ConsistentHash addresses will have to be replaced with their corresponding PersistentUUIDs
      Specified by:
      toScopedState in interface ConsistentHash
      Parameters:
      state - the state to which this ConsistentHash will be written

    • remapAddresses

      public ConsistentHash remapAddresses(UnaryOperator<Address> remapper)
      Description copied from interface: ConsistentHash
      Returns a new ConsistentHash with the addresses remapped according to the provided UnaryOperator. If an address cannot me remapped (i.e. the remapper returns null) this method should return null.
      Specified by:
      remapAddresses in interface ConsistentHash
      Parameters:
      remapper - the remapper which given an address replaces it with another one
      Returns:
      the remapped ConsistentHash or null if one of the remapped addresses is null

    • getCapacityFactors

      public Map<Address,Float> getCapacityFactors()
      Description copied from interface: ConsistentHash
      The capacity factor of each member. Determines the relative capacity of each node compared to the others. If null, all the members are assumed to have a capacity factor of 1.
      Specified by:
      getCapacityFactors in interface ConsistentHash

    • toString

      public String toString()
      Overrides:
      toString in class Object

    • hashCode

      public int hashCode()
      Overrides:
      hashCode in class Object

    • equals

      public boolean equals(Object obj)
      Overrides:
      equals in class Object