edu.ucsb.nceas.metacat.dataone.hazelcast

Class HazelcastService

java.lang.Object

edu.ucsb.nceas.metacat.shared.BaseService

edu.ucsb.nceas.metacat.dataone.hazelcast.HazelcastService

All Implemented Interfaces:

com.hazelcast.core.EntryListener<org.dataone.service.types.v1.Identifier,org.dataone.service.types.v2.SystemMetadata>, com.hazelcast.core.ItemListener<org.dataone.service.types.v1.Identifier>, com.hazelcast.core.LifecycleListener, com.hazelcast.core.MembershipListener, java.util.EventListener

public class HazelcastService
extends BaseService
implements com.hazelcast.core.EntryListener<org.dataone.service.types.v1.Identifier,org.dataone.service.types.v2.SystemMetadata>, com.hazelcast.core.MembershipListener, com.hazelcast.core.LifecycleListener, com.hazelcast.core.ItemListener<org.dataone.service.types.v1.Identifier>

The Hazelcast service enables Metacat as a Hazelcast cluster member

Field Summary

Fields inherited from class edu.ucsb.nceas.metacat.shared.BaseService

_serviceName

Method Summary

Modifier and Type	Method and Description
protected void	doRefresh() Refresh the Hazelcast service by restarting it
void	entryAdded(com.hazelcast.core.EntryEvent<org.dataone.service.types.v1.Identifier,org.dataone.service.types.v2.SystemMetadata> event) Implement the EntryListener interface for Hazelcast, reponding to entry added events in the hzSystemMetadata map.
void	entryEvicted(com.hazelcast.core.EntryEvent<org.dataone.service.types.v1.Identifier,org.dataone.service.types.v2.SystemMetadata> event) Implement the EntryListener interface for Hazelcast, reponding to entry evicted events in the hzSystemMetadata map.
void	entryRemoved(com.hazelcast.core.EntryEvent<org.dataone.service.types.v1.Identifier,org.dataone.service.types.v2.SystemMetadata> event) Implement the EntryListener interface for Hazelcast, reponding to entry removed events in the hzSystemMetadata map.
void	entryUpdated(com.hazelcast.core.EntryEvent<org.dataone.service.types.v1.Identifier,org.dataone.service.types.v2.SystemMetadata> event) Implement the EntryListener interface for Hazelcast, reponding to entry updated events in the hzSystemMetadata map.
com.hazelcast.core.HazelcastInstance	getHazelcastInstance()
com.hazelcast.core.ISet<org.dataone.service.types.v1.Identifier>	getIdentifiers() Get the identifiers set
com.hazelcast.core.IMap<org.dataone.service.types.v1.Identifier,edu.ucsb.nceas.metacat.common.index.event.IndexEvent>	getIndexEventMap() Get the index event map
com.hazelcast.core.IMap<org.dataone.service.types.v1.Identifier,edu.ucsb.nceas.metacat.common.index.IndexTask>	getIndexQueue() Get the index queue
static HazelcastService	getInstance() Get the instance of the HazelcastService that has been instantiated, or instantiate one if it has not been already.
java.util.concurrent.locks.Lock	getLock(java.lang.String identifier)
com.hazelcast.core.IMap<org.dataone.service.types.v1.Identifier,org.dataone.service.types.v2.SystemMetadata>	getSystemMetadataMap() Get the system metadata map
void	init() Initializes the Hazelcast service
void	itemAdded(com.hazelcast.core.ItemEvent<org.dataone.service.types.v1.Identifier> event) Respond to itemAdded events on the hzMissingIdentifiers Set.
void	itemRemoved(com.hazelcast.core.ItemEvent<org.dataone.service.types.v1.Identifier> event) Respond to itemRemoved events on the hzMissingIdentifiers Set
void	memberAdded(com.hazelcast.core.MembershipEvent event) When there is missing SystemMetadata on the local member, we retrieve it from the shared map and add it to the local backing store for safe keeping.
void	memberRemoved(com.hazelcast.core.MembershipEvent event)
boolean	refreshable() Indicate whether or not this service is refreshable.
void	refreshSystemMetadataEntry(java.lang.String guid) When Metacat changes the underlying store, we need to refresh the in-memory representation of it.
void	resynchInThread()
void	stateChanged(com.hazelcast.core.LifecycleEvent event) In cases where this cluster is paused, we want to check that the local store accurately reflects the shared SystemMetadata map
void	stop() Stop the HazelcastService.

Methods inherited from class edu.ucsb.nceas.metacat.shared.BaseService

refresh

Methods inherited from class java.lang.Object

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

Method Detail

getInstance

public static HazelcastService getInstance()

Get the instance of the HazelcastService that has been instantiated, or instantiate one if it has not been already.

Returns:

hazelcastService - The instance of the hazelcast service

init

public void init()
          throws ServiceException

Initializes the Hazelcast service

Throws:

ServiceException

getSystemMetadataMap

public com.hazelcast.core.IMap<org.dataone.service.types.v1.Identifier,org.dataone.service.types.v2.SystemMetadata> getSystemMetadataMap()

Get the system metadata map

Parameters:

identifier - - the identifier of the object as a string

Returns:

systemMetadata - the hazelcast map of system metadata

getIdentifiers

public com.hazelcast.core.ISet<org.dataone.service.types.v1.Identifier> getIdentifiers()

Get the identifiers set

Returns:

identifiers - the set of unique DataONE identifiers in the cluster

getIndexQueue

public com.hazelcast.core.IMap<org.dataone.service.types.v1.Identifier,edu.ucsb.nceas.metacat.common.index.IndexTask> getIndexQueue()

Get the index queue

Returns:

the set of SystemMetadata to be indexed

getIndexEventMap

public com.hazelcast.core.IMap<org.dataone.service.types.v1.Identifier,edu.ucsb.nceas.metacat.common.index.event.IndexEvent> getIndexEventMap()

Get the index event map

Returns:

indexEventMap - the hazelcast map of index events

refreshSystemMetadataEntry

public void refreshSystemMetadataEntry(java.lang.String guid)

When Metacat changes the underlying store, we need to refresh the in-memory representation of it.

Parameters:

guid -

getLock

public java.util.concurrent.locks.Lock getLock(java.lang.String identifier)

refreshable

public boolean refreshable()

Indicate whether or not this service is refreshable.

Specified by:

refreshable in class BaseService

Returns:

refreshable - the boolean refreshable status

stop

public void stop()
          throws ServiceException

Stop the HazelcastService. When stopped, the service will no longer respond to requests.

Specified by:

stop in class BaseService

Throws:

ServiceException

getHazelcastInstance

public com.hazelcast.core.HazelcastInstance getHazelcastInstance()

doRefresh

protected void doRefresh()
                  throws ServiceException

Refresh the Hazelcast service by restarting it

Specified by:

doRefresh in class BaseService

Throws:

ServiceException

entryAdded

public void entryAdded(com.hazelcast.core.EntryEvent<org.dataone.service.types.v1.Identifier,org.dataone.service.types.v2.SystemMetadata> event)

Implement the EntryListener interface for Hazelcast, reponding to entry added events in the hzSystemMetadata map. Evaluate the entry and create CNReplicationTasks as appropriate (for DATA, METADATA, RESOURCE)

Specified by:

entryAdded in interface com.hazelcast.core.EntryListener<org.dataone.service.types.v1.Identifier,org.dataone.service.types.v2.SystemMetadata>

Parameters:

event - - The EntryEvent that occurred

entryEvicted

public void entryEvicted(com.hazelcast.core.EntryEvent<org.dataone.service.types.v1.Identifier,org.dataone.service.types.v2.SystemMetadata> event)

Implement the EntryListener interface for Hazelcast, reponding to entry evicted events in the hzSystemMetadata map. Evaluate the entry and create CNReplicationTasks as appropriate (for DATA, METADATA, RESOURCE)

Specified by:

entryEvicted in interface com.hazelcast.core.EntryListener<org.dataone.service.types.v1.Identifier,org.dataone.service.types.v2.SystemMetadata>

Parameters:

event - - The EntryEvent that occurred

entryRemoved

public void entryRemoved(com.hazelcast.core.EntryEvent<org.dataone.service.types.v1.Identifier,org.dataone.service.types.v2.SystemMetadata> event)

Implement the EntryListener interface for Hazelcast, reponding to entry removed events in the hzSystemMetadata map. Evaluate the entry and create CNReplicationTasks as appropriate (for DATA, METADATA, RESOURCE)

Specified by:

entryRemoved in interface com.hazelcast.core.EntryListener<org.dataone.service.types.v1.Identifier,org.dataone.service.types.v2.SystemMetadata>

Parameters:

event - - The EntryEvent that occurred

entryUpdated

public void entryUpdated(com.hazelcast.core.EntryEvent<org.dataone.service.types.v1.Identifier,org.dataone.service.types.v2.SystemMetadata> event)

Implement the EntryListener interface for Hazelcast, reponding to entry updated events in the hzSystemMetadata map. Evaluate the entry and create CNReplicationTasks as appropriate (for DATA, METADATA, RESOURCE)

Specified by:

entryUpdated in interface com.hazelcast.core.EntryListener<org.dataone.service.types.v1.Identifier,org.dataone.service.types.v2.SystemMetadata>

Parameters:

event - - The EntryEvent that occurred

resynchInThread

public void resynchInThread()

memberAdded

public void memberAdded(com.hazelcast.core.MembershipEvent event)

When there is missing SystemMetadata on the local member, we retrieve it from the shared map and add it to the local backing store for safe keeping.

Specified by:

memberAdded in interface com.hazelcast.core.MembershipListener

memberRemoved

public void memberRemoved(com.hazelcast.core.MembershipEvent event)

Specified by:

memberRemoved in interface com.hazelcast.core.MembershipListener

stateChanged

public void stateChanged(com.hazelcast.core.LifecycleEvent event)

In cases where this cluster is paused, we want to check that the local store accurately reflects the shared SystemMetadata map

Specified by:

stateChanged in interface com.hazelcast.core.LifecycleListener

Parameters:

event -

itemAdded

public void itemAdded(com.hazelcast.core.ItemEvent<org.dataone.service.types.v1.Identifier> event)

Respond to itemAdded events on the hzMissingIdentifiers Set. Uses a distributed ILock to try to prevent multiple put calls on hzSystemMetadata

Specified by:

itemAdded in interface com.hazelcast.core.ItemListener<org.dataone.service.types.v1.Identifier>

Parameters:

pid - the identifier of the event

itemRemoved

public void itemRemoved(com.hazelcast.core.ItemEvent<org.dataone.service.types.v1.Identifier> event)

Respond to itemRemoved events on the hzMissingIdentifiers Set

Specified by:

itemRemoved in interface com.hazelcast.core.ItemListener<org.dataone.service.types.v1.Identifier>

Parameters:

pid - the identifier of the event