Package org.infinispan.distribution.ch.impl

Class ScatteredConsistentHashFactory

java.lang.Object

org.infinispan.distribution.ch.impl.AbstractConsistentHashFactory<ScatteredConsistentHash>

org.infinispan.distribution.ch.impl.ScatteredConsistentHashFactory

All Implemented Interfaces:

ConsistentHashFactory<ScatteredConsistentHash>

public class ScatteredConsistentHashFactory
extends AbstractConsistentHashFactory<ScatteredConsistentHash>

Based on DefaultConsistentHashFactory.

Since:

9.0

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
protected static class	ScatteredConsistentHashFactory.Builder
static class	ScatteredConsistentHashFactory.Externalizer

Constructor Summary

Constructors

Constructor	Description
ScatteredConsistentHashFactory()

Method Summary

Modifier and Type	Method	Description
ScatteredConsistentHash	create(org.infinispan.commons.hash.Hash hashFunction, int numOwners, int numSegments, List<Address> members, Map<Address,Float> capacityFactors)	Create a new consistent hash instance.
boolean	equals(Object other)
ScatteredConsistentHash	fromPersistentState(ScopedPersistentState state)	Recreates a ConsistentHash from a previously stored persistent state.
int	hashCode()
ScatteredConsistentHash	rebalance(ScatteredConsistentHash baseCH)	Create a new consistent hash instance, based on an existing instance, but balanced according to the implementation's rules.
protected void	rebalanceBuilder(ScatteredConsistentHashFactory.Builder builder)
protected void	replacePrimaryOwners(ScatteredConsistentHashFactory.Builder builder)
ScatteredConsistentHash	union(ScatteredConsistentHash dch1, ScatteredConsistentHash dch2)	Merges two consistent hash objects that have the same number of segments, numOwners and hash function.
ScatteredConsistentHash	updateMembers(ScatteredConsistentHash baseCH, List<Address> actualMembers, Map<Address,Float> actualCapacityFactors)	Leavers are removed and segments without owners are assigned new owners.

Methods inherited from class org.infinispan.distribution.ch.impl.AbstractConsistentHashFactory

checkCapacityFactors, findNewPrimaryOwner, findWorstPrimaryOwner

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ScatteredConsistentHashFactory

public ScatteredConsistentHashFactory()

Method Detail

create

public ScatteredConsistentHash create(org.infinispan.commons.hash.Hash hashFunction,
                                      int numOwners,
                                      int numSegments,
                                      List<Address> members,
                                      Map<Address,Float> capacityFactors)

Description copied from interface: ConsistentHashFactory

Create a new consistent hash instance. The consistent hash will be balanced.

Parameters:

hashFunction - The hash function to use on top of the keys' own hashCode() implementation.

numOwners - The ideal number of owners for each key. The created consistent hash can have more or less owners, but each key will have at least one owner.

numSegments - Number of hash-space segments. The implementation may round up the number of segments for performance, or may ignore the parameter altogether.

members - A list of addresses representing the new cache members.

capacityFactors - The capacity factor of each member. Determines the relative capacity of each node compared to the others. The implementation may ignore this parameter. If null, all the members are assumed to have a capacity factor of 1.

fromPersistentState

public ScatteredConsistentHash fromPersistentState(ScopedPersistentState state)

Description copied from interface: ConsistentHashFactory

Recreates a ConsistentHash from a previously stored persistent state. The returned ConsistentHash will not have proper addresses, but PersistentUUIDs instead so they will need to be replaced

Parameters:

state - the state to restore

updateMembers

public ScatteredConsistentHash updateMembers(ScatteredConsistentHash baseCH,
                                             List<Address> actualMembers,
                                             Map<Address,Float> actualCapacityFactors)

Leavers are removed and segments without owners are assigned new owners. Joiners might get some of the un-owned segments but otherwise they are not taken into account (that should happen during a rebalance).

Parameters:

baseCH - An existing consistent hash instance, should not be null

actualMembers - A list of addresses representing the new cache members.

actualCapacityFactors - The capacity factor of each member. Determines the relative capacity of each node compared to the others. The implementation may ignore this parameter. If null, all the members are assumed to have a capacity factor of 1.

Returns:

rebalance

public ScatteredConsistentHash rebalance(ScatteredConsistentHash baseCH)

Description copied from interface: ConsistentHashFactory

Create a new consistent hash instance, based on an existing instance, but balanced according to the implementation's rules.

Parameters:

baseCH - An existing consistent hash instance, should not be null

Returns:

A new ConsistentHash instance, or baseCH if the existing instance does not need any changes.

union

public ScatteredConsistentHash union(ScatteredConsistentHash dch1,
                                     ScatteredConsistentHash dch2)

Merges two consistent hash objects that have the same number of segments, numOwners and hash function. For each segment, the primary owner of the first CH has priority, the other primary owners become backups.

rebalanceBuilder

protected void rebalanceBuilder(ScatteredConsistentHashFactory.Builder builder)

replacePrimaryOwners

protected void replacePrimaryOwners(ScatteredConsistentHashFactory.Builder builder)

equals

public boolean equals(Object other)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object