org.jgroups.blocks
Class PartitionedHashMap.ConsistentHashFunction<K>

java.lang.Object
  extended by org.jgroups.blocks.MembershipListenerAdapter
      extended by org.jgroups.blocks.PartitionedHashMap.ConsistentHashFunction<K>
All Implemented Interfaces:
PartitionedHashMap.HashFunction<K>, MembershipListener
Enclosing class:
PartitionedHashMap<K,V>

public static class PartitionedHashMap.ConsistentHashFunction<K>
extends MembershipListenerAdapter
implements PartitionedHashMap.HashFunction<K>


Field Summary
 
Fields inherited from class org.jgroups.blocks.MembershipListenerAdapter
membershipListeners, membershipListenersCache
 
Constructor Summary
PartitionedHashMap.ConsistentHashFunction()
           
 
Method Summary
 Address hash(K key, java.util.List<Address> members)
          Defines a hash function to pick the right node from the list of cluster nodes.
 void viewAccepted(View new_view)
          Notify membership listener that new view was accepted.
 
Methods inherited from class org.jgroups.blocks.MembershipListenerAdapter
addMembershipListener, block, removeMembershipListener, suspect, unblock
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

PartitionedHashMap.ConsistentHashFunction

public PartitionedHashMap.ConsistentHashFunction()
Method Detail

hash

public Address hash(K key,
                    java.util.List<Address> members)
Description copied from interface: PartitionedHashMap.HashFunction
Defines a hash function to pick the right node from the list of cluster nodes. Ideally, this function uses consistent hashing, so that the same key maps to the same node despite cluster view changes. If a view change causes all keys to hash to different nodes, then PartitionedHashMap will redirect requests to different nodes and this causes unnecessary overhead.

Specified by:
hash in interface PartitionedHashMap.HashFunction<K>
Parameters:
key - The object to be hashed
members - The membership. This value can be ignored for example if the hash function keeps track of the membership itself, e.g. by registering as a membership listener (PartitionedHashMap.addMembershipListener(org.jgroups.MembershipListener) )
Returns:

viewAccepted

public void viewAccepted(View new_view)
Description copied from class: MembershipListenerAdapter
Notify membership listener that new view was accepted. This method in turn passes new view to all registered membership listeners.

Specified by:
viewAccepted in interface MembershipListener
Overrides:
viewAccepted in class MembershipListenerAdapter


Copyright © 1998-2009 Bela Ban / Red Hat. All Rights Reserved.