Package com.yugabyte.ysql

Class ClusterAwareLoadBalancer

java.lang.Object

com.yugabyte.ysql.ClusterAwareLoadBalancer

All Implemented Interfaces:

LoadBalancer

public class ClusterAwareLoadBalancer
extends Object
implements LoadBalancer

Field Summary

Fields

Modifier and Type	Field	Description
protected static final Logger	LOGGER
protected int	refreshListSeconds

Constructor Summary

Constructors

Constructor	Description
ClusterAwareLoadBalancer(LoadBalanceService.LoadBalanceType lb, int refreshInterval)

Method Summary

Modifier and Type	Method	Description
static ClusterAwareLoadBalancer	getInstance(LoadBalanceService.LoadBalanceType lb, int refreshListSeconds)
String	getLeastLoadedServer(boolean newRequest, List<String> failedHosts, ArrayList<String> timedOutHosts)
int	getRefreshListSeconds()
boolean	isHostEligible(Map.Entry<String,LoadBalanceService.NodeInfo> e, Byte requestFlags)
String	toString()

Methods inherited from class java.lang.Object

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

Field Details

LOGGER

protected static final Logger LOGGER

refreshListSeconds

protected int refreshListSeconds

Constructor Details

ClusterAwareLoadBalancer

public ClusterAwareLoadBalancer(LoadBalanceService.LoadBalanceType lb,
 int refreshInterval)

Method Details

getRefreshListSeconds

public int getRefreshListSeconds()

Specified by:

getRefreshListSeconds in interface LoadBalancer

Returns:

the value of the property "yb-servers-refresh-interval" specified either in the url or as a property

getInstance

public static ClusterAwareLoadBalancer getInstance(LoadBalanceService.LoadBalanceType lb,
 int refreshListSeconds)

toString

public String toString()

Overrides:

toString in class Object

isHostEligible

public boolean isHostEligible(Map.Entry<String,LoadBalanceService.NodeInfo> e,
 Byte requestFlags)

Specified by:

isHostEligible in interface LoadBalancer

Parameters:

e - The LoadBalanceService.NodeInfo object for the host

requestFlags - The attributes for the load balancer to make use of

Returns:

true, if a host is eligible to be considered for a connection request

getLeastLoadedServer

public String getLeastLoadedServer(boolean newRequest,
 List<String> failedHosts,
 ArrayList<String> timedOutHosts)

Specified by:

getLeastLoadedServer in interface LoadBalancer

Parameters:

newRequest - whether this invocation is first for a new connection request

failedHosts - list of host names which have been known to be down

timedOutHosts - list of host names where connections were attempted but timed out

Returns:

the name of a host with the least number of connections, as per the driver's stats