All Known Implementing Classes:

PreferAvailabilityStrategy, PreferConsistencyStrategy
```
public interface AvailabilityStrategy
```
Implementations decide what to do when the cache membership changes, either because new nodes joined, nodes left, or there was a merge. The decision is then applied by calling one of the AvailabilityStrategyContext methods. The strategy can also queue actions until the current rebalance ends, and execute them on onRebalanceEnd(AvailabilityStrategyContext). Method invocations are synchronized, so it's not possible to have concurrent invocations.

Since:

7.0

Author:

Mircea Markus, Dan Berindei

Method Summary

All Methods Static Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`void`	`onClusterViewChange(AvailabilityStrategyContext context, List<Address> clusterMembers)`	Called when the cluster view changed (e.g.
`void`	`onGracefulLeave(AvailabilityStrategyContext context, Address leaver)`	Called when a node leaves gracefully.
`void`	`onJoin(AvailabilityStrategyContext context, Address joiner)`	Called when a node joins.
`void`	`onManualAvailabilityChange(AvailabilityStrategyContext context, AvailabilityMode newAvailabilityMode)`	Called when the administrator manually changes the availability status.
`void`	`onPartitionMerge(AvailabilityStrategyContext context, Map<Address,CacheStatusResponse> statusResponseMap)`	Called when two or more partitions merge, to compute the stable and current cache topologies for the merged cluster.
`void`	`onRebalanceEnd(AvailabilityStrategyContext context)`	Called when a rebalance ends.
`static ConsistentHash`	`ownersConsistentHash(CacheTopology topology, ConsistentHashFactory chFactory)`	Compute the read consistent hash for a topology with a `null` union consistent hash.

Method Detail

ownersConsistentHash

static ConsistentHash ownersConsistentHash(CacheTopology topology,
                                           ConsistentHashFactory chFactory)

Compute the read consistent hash for a topology with a null union consistent hash. Originally a copy of CacheTopology.getReadConsistentHash() but differs in case of scattered cache.

onJoin

void onJoin(AvailabilityStrategyContext context,
            Address joiner)

Called when a node joins.

onGracefulLeave

void onGracefulLeave(AvailabilityStrategyContext context,
                     Address leaver)

Called when a node leaves gracefully.

onClusterViewChange

void onClusterViewChange(AvailabilityStrategyContext context,
                         List<Address> clusterMembers)

Called when the cluster view changed (e.g. because one or more nodes left abruptly).

onPartitionMerge

void onPartitionMerge(AvailabilityStrategyContext context,
                      Map<Address,CacheStatusResponse> statusResponseMap)

Called when two or more partitions merge, to compute the stable and current cache topologies for the merged cluster.

onRebalanceEnd
```
void onRebalanceEnd(AvailabilityStrategyContext context)
```
Called when a rebalance ends. Can be used to re-assess the state of the cache and apply pending changes.

onManualAvailabilityChange

void onManualAvailabilityChange(AvailabilityStrategyContext context,
                                AvailabilityMode newAvailabilityMode)

Called when the administrator manually changes the availability status.

Interface AvailabilityStrategy