com.hazelcast.crdt.pncounter

Class PNCounterService

java.lang.Object

com.hazelcast.crdt.pncounter.PNCounterService

All Implemented Interfaces:

CRDTReplicationAwareService<PNCounterImpl>, ManagedService, QuorumAwareService, RemoteService, StatisticsAwareService<LocalPNCounterStats>

public class PNCounterService
extends Object
implements ManagedService, RemoteService, CRDTReplicationAwareService<PNCounterImpl>, QuorumAwareService, StatisticsAwareService<LocalPNCounterStats>

Service responsible for PNCounter proxies and replication operation.

Field Summary

Fields

Modifier and Type	Field and Description
static String	SERVICE_NAME The name under which this service is registered

Constructor Summary

Constructors

Constructor and Description
PNCounterService()

Method Summary

Modifier and Type	Method and Description
boolean	clearCRDTState(Map<String,VectorClock> vectorClocks) Removes all of the CRDTs with vector clocks equal to the provided vector clocks.
boolean	containsCounter(String name) Returns true if the CRDT state for the PN counter with the given name is present on this node.
PNCounterProxy	createDistributedObject(String objectName) Creates a distributed object.
void	destroyDistributedObject(String objectName) Destroys a distributed object.
PNCounterImpl	getCounter(String name) Returns the counter with the given name.
LocalPNCounterStatsImpl	getLocalPNCounterStats(String name) Returns the PN counter statistics for the counter with the given name
String	getName() Returns the name of the service
String	getQuorumName(String name) Gets the name of the quorum associated with specified operation name.
Map<String,LocalPNCounterStats>	getStats() Return the service statistics for the local instance.
void	init(NodeEngine nodeEngine, Properties properties) Initializes this service.
void	merge(String name, PNCounterImpl value) Performs a merge of the local name CRDT with the provided state.
CRDTReplicationContainer	prepareMigrationOperation(int maxConfiguredReplicaCount) Returns a migration operation for all of the CRDT states not owned by this member.
CRDTReplicationContainer	prepareReplicationOperation(Map<String,VectorClock> previouslyReplicatedVectorClocks, int targetIndex) Returns a replication operation for the provided vector clocks.
void	prepareToSafeShutdown() Prepares the service for replication and shutdown.
void	reset() Resets this service back to its initial state.
void	shutdown(boolean terminate) Shuts down this service.

Methods inherited from class java.lang.Object

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

Field Detail

SERVICE_NAME

public static final String SERVICE_NAME

The name under which this service is registered

See Also:

Constant Field Values

Constructor Detail

PNCounterService

public PNCounterService()

Method Detail

getCounter

public PNCounterImpl getCounter(String name)

Returns the counter with the given name.

containsCounter

public boolean containsCounter(String name)

Returns true if the CRDT state for the PN counter with the given name is present on this node.

Parameters:

name - the PN counter name

getLocalPNCounterStats

public LocalPNCounterStatsImpl getLocalPNCounterStats(String name)

Returns the PN counter statistics for the counter with the given name

init

public void init(NodeEngine nodeEngine,
                 Properties properties)

Description copied from interface: ManagedService

Initializes this service.

Specified by:

init in interface ManagedService

Parameters:

nodeEngine - the NodeEngine that this service belongs to

properties - the Properties (can be used to pass settings to the service)

reset

public void reset()

Description copied from interface: ManagedService

Resets this service back to its initial state.

TODO: what is the purpose of reset

Specified by:

reset in interface ManagedService

shutdown

public void shutdown(boolean terminate)

Description copied from interface: ManagedService

Shuts down this service.

TODO: what is the purpose of the terminate variable

Specified by:

shutdown in interface ManagedService

Parameters:

terminate - true to shut down this service

createDistributedObject

public PNCounterProxy createDistributedObject(String objectName)

Description copied from interface: RemoteService

Creates a distributed object.

Specified by:

createDistributedObject in interface RemoteService

Parameters:

objectName - the name for the created distributed object

Returns:

the created distributed object

destroyDistributedObject

public void destroyDistributedObject(String objectName)

Description copied from interface: RemoteService

Destroys a distributed object.

Specified by:

destroyDistributedObject in interface RemoteService

Parameters:

objectName - the name of the distributed object to destroy

prepareReplicationOperation

public CRDTReplicationContainer prepareReplicationOperation(Map<String,VectorClock> previouslyReplicatedVectorClocks,
                                                            int targetIndex)

Description copied from interface: CRDTReplicationAwareService

Returns a replication operation for the provided vector clocks. The vector clock map contains mappings from CRDT name to the last successfully replicated CRDT vector clock. All CRDTs in this map should be of the same type. A return value of null means that there should not be any replication operation.

Specified by:

prepareReplicationOperation in interface CRDTReplicationAwareService<PNCounterImpl>

Parameters:

previouslyReplicatedVectorClocks - last successfully replicated vector clock

targetIndex - the index of the replication target in the membership list containing only data members

Returns:

the replication operation and the replicated vector clocks

getName

public String getName()

Description copied from interface: CRDTReplicationAwareService

Returns the name of the service

Specified by:

getName in interface CRDTReplicationAwareService<PNCounterImpl>

merge

public void merge(String name,
                  PNCounterImpl value)

Description copied from interface: CRDTReplicationAwareService

Performs a merge of the local name CRDT with the provided state.

Specified by:

merge in interface CRDTReplicationAwareService<PNCounterImpl>

Parameters:

name - the CRDT name

value - the CRDT state to merge into the local state

prepareMigrationOperation

public CRDTReplicationContainer prepareMigrationOperation(int maxConfiguredReplicaCount)

Description copied from interface: CRDTReplicationAwareService

Returns a migration operation for all of the CRDT states not owned by this member.

Specified by:

prepareMigrationOperation in interface CRDTReplicationAwareService<PNCounterImpl>

Parameters:

maxConfiguredReplicaCount - the maximum configured replica count for the CRDTs to be migrated (excluding)

Returns:

the migration operation and the current vector clocks

clearCRDTState

public boolean clearCRDTState(Map<String,VectorClock> vectorClocks)

Description copied from interface: CRDTReplicationAwareService

Removes all of the CRDTs with vector clocks equal to the provided vector clocks. The vector clock map contains mappings from CRDT name to a vector clock. All CRDTs in this map should be of the same type.

Specified by:

clearCRDTState in interface CRDTReplicationAwareService<PNCounterImpl>

Parameters:

vectorClocks - a map from CRDT name to a vector clock

Returns:

true if all of the CRDT states have been cleared, false otherwise

prepareToSafeShutdown

public void prepareToSafeShutdown()

Description copied from interface: CRDTReplicationAwareService

Prepares the service for replication and shutdown. After this method has returned, no mutations must be allowed to any existing CRDT state in this service and new CRDT states must be disallowed.

Specified by:

prepareToSafeShutdown in interface CRDTReplicationAwareService<PNCounterImpl>

getQuorumName

public String getQuorumName(String name)

Description copied from interface: QuorumAwareService

Gets the name of the quorum associated with specified operation name.

Specified by:

getQuorumName in interface QuorumAwareService

Parameters:

name - the operation name for which the quorum name is retured

Returns:

name of the associated quorum, null if there is no associated quorum

getStats

public Map<String,LocalPNCounterStats> getStats()

Description copied from interface: StatisticsAwareService

Return the service statistics for the local instance.

Specified by:

getStats in interface StatisticsAwareService<LocalPNCounterStats>

Returns:

the statistics, grouped by distributed object name