org.adroitlogic.x.clustering.failover.strategy

Class GroupFailoverStrategy

java.lang.Object

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

org.adroitlogic.x.clustering.failover.strategy.GroupFailoverStrategy

All Implemented Interfaces:

org.apache.curator.framework.state.ConnectionStateListener

public class GroupFailoverStrategy
extends FailoverStrategy<GroupFailoverClusterPaths>

The failover strategy to provide failover to groups of nodes. Under this strategy, a group of nodes can be assigned to provide failover to another node group. Also a set of conditions can be specified to determine when to start providing failover to a given group. FailoverGroupConfig is the class which responsible for specifying when to start failover.

This class will be adding group names to the XEnvironment based on the decisions made on whether to start failover. The tags will be added under the key XTAG_ACTING_AS_GROUP_NAME. They will be later used by an EnvironmentEvaluator to determine whether to start/stop components.

Since:

17.01

Author:

Imesha Sudasingha

Field Summary

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

client, environment, failoverClusterPaths, status

Constructor Summary

Constructors

Constructor and Description
GroupFailoverStrategy()

Method Summary

Modifier and Type	Method and Description
Map<String,List<FailoverGroupConfig>>	getFailoverMatrix()
String	getGroupName()
protected void	initStrategy()
boolean	isFailoverOnStartup()
protected GroupFailoverClusterPaths	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	setFailoverMatrix(Map<String,List<FailoverGroupConfig>> failoverMatrix)
void	setFailoverOnStartup(boolean failoverOnStartup)
void	setGroupName(String groupName)
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

GroupFailoverStrategy

public GroupFailoverStrategy()

Method Detail

initStrategy

protected void initStrategy()

Specified by:

initStrategy in class FailoverStrategy<GroupFailoverClusterPaths>

startStrategy

protected void startStrategy()

Specified by:

startStrategy in class FailoverStrategy<GroupFailoverClusterPaths>

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<GroupFailoverClusterPaths>

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<GroupFailoverClusterPaths>

stopStrategy

protected void stopStrategy()

Specified by:

stopStrategy in class FailoverStrategy<GroupFailoverClusterPaths>

newFailoverClusterPaths

protected GroupFailoverClusterPaths newFailoverClusterPaths()

Specified by:

newFailoverClusterPaths in class FailoverStrategy<GroupFailoverClusterPaths>

getFailoverMatrix

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

Specified by:

getFailoverMatrix in class FailoverStrategy<GroupFailoverClusterPaths>

toString

public String toString()

Specified by:

toString in class FailoverStrategy<GroupFailoverClusterPaths>

setFailoverMatrix

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

isFailoverOnStartup

public boolean isFailoverOnStartup()

setFailoverOnStartup

public void setFailoverOnStartup(boolean failoverOnStartup)

getGroupName

public String getGroupName()

setGroupName

public void setGroupName(String groupName)