org.adroitlogic.x.clustering.failover.strategy

Class NodeWiseFailoverStrategy

java.lang.Object

org.adroitlogic.x.clustering.failover.strategy.FailoverStrategy<NodeWiseFailoverClusterPaths>

org.adroitlogic.x.clustering.failover.strategy.NodeWiseFailoverStrategy

All Implemented Interfaces:

org.apache.curator.framework.state.ConnectionStateListener

public class NodeWiseFailoverStrategy
extends FailoverStrategy<NodeWiseFailoverClusterPaths>

Class implementing the Node wise failover strategy. This class has the ability to failover node wise. That is, once configured this class will watch on the assigned nodes for their activeness and whenever an inactivity is detected, this class will take the corresponding measures to notify to as the assigned node.

recursivelyFailover flag is used to state whether to provide failover recursively when a node goes down. Therefore, this flag has to be used carefully. When configuring nodes, we have to make sure that the projects required to provide recursive failover is added to each node.

Since:

17.01

Author:

Imesha Sudasingha

Field Summary

Fields inherited from class org.adroitlogic.x.clustering.failover.strategy.FailoverStrategy

client, environment, failoverClusterPaths, logger, status

Constructor Summary

Constructors

Constructor and Description
NodeWiseFailoverStrategy()

Method Summary

Modifier and Type	Method and Description
int	getDistributedLockWaitTimeMs()
Map<String,List<String>>	getFailoverMatrix()
int	getWaitTimeBeforeFailoverMs()
protected void	initStrategy()
boolean	isFailoverOnStartup()
boolean	isRecursivelyFailover()
protected NodeWiseFailoverClusterPaths	newFailoverClusterPaths()
void	refresh() This method is called whenever the failover strategy believes that the connection state became unstable and again re became stable.
void	resetTags() Whenever the connection state changes to lost or suspended, this method will be called in order to remove the tags added by the extending concrete strategy.
void	setDistributedLockWaitTimeMs(int distributedLockWaitTimeMs)
void	setFailoverMatrix(Map<String,String> failoverMatrix)
void	setFailoverOnStartup(boolean failoverOnStartup)
void	setRecursivelyFailover(boolean recursivelyFailover)
void	setWaitTimeBeforeFailoverMs(int waitTimeBeforeFailoverMs)
protected void	startStrategy()
protected void	stopStrategy()
String	toString()

Methods inherited from class org.adroitlogic.x.clustering.failover.strategy.FailoverStrategy

addTags, getFailoverClusterPaths, initialize, removeTags, start, stateChanged, stop

Methods inherited from class java.lang.Object

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

Constructor Detail

NodeWiseFailoverStrategy

public NodeWiseFailoverStrategy()

Method Detail

initStrategy

protected void initStrategy()

Specified by:

initStrategy in class FailoverStrategy<NodeWiseFailoverClusterPaths>

startStrategy

protected void startStrategy()

Specified by:

startStrategy in class FailoverStrategy<NodeWiseFailoverClusterPaths>

refresh

public void refresh()

This method is called whenever the failover strategy believes that the connection state became unstable and again re became stable. In such occasions the implementation might need to recheck for interested ZNodes and identity the needs of providing failover.

Specified by:

refresh in class FailoverStrategy<NodeWiseFailoverClusterPaths>

resetTags

public void resetTags()

Whenever the connection state changes to lost or suspended, this method will be called in order to remove the tags added by the extending concrete strategy. Therefore, the classes implementing this method should make sure that no tags added by that class is in the environment anymore by removing them if they exist.

Specified by:

resetTags in class FailoverStrategy<NodeWiseFailoverClusterPaths>

stopStrategy

protected void stopStrategy()

Specified by:

stopStrategy in class FailoverStrategy<NodeWiseFailoverClusterPaths>

getFailoverMatrix

public Map<String,List<String>> getFailoverMatrix()

Specified by:

getFailoverMatrix in class FailoverStrategy<NodeWiseFailoverClusterPaths>

toString

public String toString()

Specified by:

toString in class FailoverStrategy<NodeWiseFailoverClusterPaths>

setFailoverMatrix

public void setFailoverMatrix(Map<String,String> failoverMatrix)

newFailoverClusterPaths

protected NodeWiseFailoverClusterPaths newFailoverClusterPaths()

Specified by:

newFailoverClusterPaths in class FailoverStrategy<NodeWiseFailoverClusterPaths>

getDistributedLockWaitTimeMs

public int getDistributedLockWaitTimeMs()

setDistributedLockWaitTimeMs

public void setDistributedLockWaitTimeMs(int distributedLockWaitTimeMs)

getWaitTimeBeforeFailoverMs

public int getWaitTimeBeforeFailoverMs()

setWaitTimeBeforeFailoverMs

public void setWaitTimeBeforeFailoverMs(int waitTimeBeforeFailoverMs)

isFailoverOnStartup

public boolean isFailoverOnStartup()

setFailoverOnStartup

public void setFailoverOnStartup(boolean failoverOnStartup)

isRecursivelyFailover

public boolean isRecursivelyFailover()

setRecursivelyFailover

public void setRecursivelyFailover(boolean recursivelyFailover)