org.eclipse.smila.zookeeper.internal
Class ZooKeeperServiceImpl

java.lang.Object
  org.eclipse.smila.zookeeper.internal.ZooKeeperServiceImpl

All Implemented Interfaces:

ZooKeeperService

public class ZooKeeperServiceImpl
extends java.lang.Object
implements ZooKeeperService

OSGi services that configures and starts a ZooKeeper, either stand-alone if we are not running in a multi-node cluster or without ClusterConfigService at all or as distributed on the complete cluster.

Field Summary

Fields inherited from interface org.eclipse.smila.zookeeper.ZooKeeperService

BUNDLE_ID

Constructor Summary

ZooKeeperServiceImpl()

Method Summary

protected void	activate(ComponentContext context) OSGi Declarative Services service activation method.
void	closeClient() close the client quietly.
protected void	deactivate(ComponentContext context) OSGi Declarative Services service deactivation method.
ZooKeeper	getClient() get zookeeper client, create if it doesn't exist.
long	getFailSafetyLevel()
AnyMap	getServerState()
boolean	isOperational()
void	process(WatchedEvent event) we only use Watches for zookeeper client state change events.
void	registerWatcher(Watcher watcher) register a watcher for ZooKeeper events.
void	setClusterConfigService(ClusterConfigService clusterConfigService) set new ClusterConfigService.
void	setEnvironmentInfo(EnvironmentInfo environmentInfo) set new EnvironmentInfo.
void	unregisterWatcher(Watcher watcher) unregister a watcher for ZooKeeper events.
void	unsetClusterConfigService(ClusterConfigService clusterConfigService) remove a ClusterConfigService.
void	unsetEnvironmentInfo(EnvironmentInfo environmentInfo) remove a EnvironmentInfo.
void	waitForClientConnected() wait until the zookeeper client is (re)connected.

Methods inherited from class java.lang.Object

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

Constructor Detail

ZooKeeperServiceImpl

public ZooKeeperServiceImpl()

Method Detail

getClient

public ZooKeeper getClient()
                    throws java.io.IOException,
                           ClusterConfigException

get zookeeper client, create if it doesn't exist.

Specified by:

getClient in interface ZooKeeperService

Returns:

client

Throws:

java.io.IOException - error creating client

ClusterConfigException - if the cluster configuration cannot be read

closeClient

public void closeClient()

close the client quietly.

Specified by:

closeClient in interface ZooKeeperService

getFailSafetyLevel

public long getFailSafetyLevel()

Specified by:

getFailSafetyLevel in interface ZooKeeperService

Returns:

number of nodes that may fail without ZooKeeper service stopping to work.

activate

protected void activate(ComponentContext context)

OSGi Declarative Services service activation method.

Parameters:

context - OSGi service component context.

deactivate

protected void deactivate(ComponentContext context)

OSGi Declarative Services service deactivation method.

Parameters:

context - OSGi service component context.

setClusterConfigService

public void setClusterConfigService(ClusterConfigService clusterConfigService)

set new ClusterConfigService. To be called by DS runtime before activation.

Parameters:

clusterConfigService - new ClusterConfigService

unsetClusterConfigService

public void unsetClusterConfigService(ClusterConfigService clusterConfigService)

remove a ClusterConfigService. To be called by DS runtime after deactivation.

setEnvironmentInfo

public void setEnvironmentInfo(EnvironmentInfo environmentInfo)

set new EnvironmentInfo. To be called by DS runtime before activation.

Parameters:

clusterConfigService - new ClusterConfigService

unsetEnvironmentInfo

public void unsetEnvironmentInfo(EnvironmentInfo environmentInfo)

remove a EnvironmentInfo. To be called by DS runtime after deactivation.

waitForClientConnected

public void waitForClientConnected()

Description copied from interface: ZooKeeperService

wait until the zookeeper client is (re)connected.

Specified by:

waitForClientConnected in interface ZooKeeperService

process

public void process(WatchedEvent event)

we only use Watches for zookeeper client state change events.

registerWatcher

public void registerWatcher(Watcher watcher)

register a watcher for ZooKeeper events.

Specified by:

registerWatcher in interface ZooKeeperService

unregisterWatcher

public void unregisterWatcher(Watcher watcher)

unregister a watcher for ZooKeeper events.

Specified by:

unregisterWatcher in interface ZooKeeperService

getServerState

public AnyMap getServerState()

Specified by:

getServerState in interface ZooKeeperService

Returns:

zookeeper server/cluster state for monitoring.

isOperational

public boolean isOperational()

Specified by:

isOperational in interface ZooKeeperService

Returns:

'true' if zookeeper (cluster) is in a state to answer requests, 'false' otherwise.