com.netflix.loadbalancer

Class BaseLoadBalancer

java.lang.Object

com.netflix.loadbalancer.AbstractLoadBalancer

com.netflix.loadbalancer.BaseLoadBalancer

All Implemented Interfaces:

com.netflix.client.IClientConfigAware, PrimeConnections.PrimeConnectionListener, ILoadBalancer

Direct Known Subclasses:

DynamicServerListLoadBalancer

public class BaseLoadBalancer
extends AbstractLoadBalancer
implements PrimeConnections.PrimeConnectionListener, com.netflix.client.IClientConfigAware

A basic implementation of the load balancer where an arbitrary list of servers can be set as the server pool. A ping can be set to determine the liveness of a server. Internally, this class maintains an "all" server list and an "up" server list and use them depending on what the caller asks for.

Nested Class Summary

Nested classes/interfaces inherited from class com.netflix.loadbalancer.AbstractLoadBalancer

AbstractLoadBalancer.ServerGroup

Nested classes/interfaces inherited from interface com.netflix.client.IClientConfigAware

com.netflix.client.IClientConfigAware.Factory

Field Summary

Fields

Modifier and Type	Field and Description
protected java.util.List<Server>	allServerList
protected java.util.concurrent.locks.ReadWriteLock	allServerLock
protected LoadBalancerStats	lbStats
protected java.util.Timer	lbTimer
protected int	maxTotalPingTimeSeconds
protected java.lang.String	name
protected IPing	ping
protected java.util.concurrent.atomic.AtomicBoolean	pingInProgress
protected int	pingIntervalSeconds
protected IPingStrategy	pingStrategy
protected IRule	rule
protected java.util.Comparator<Server>	serverComparator
protected java.util.List<Server>	upServerList
protected java.util.concurrent.locks.ReadWriteLock	upServerLock

Constructor Summary

Constructors

Constructor and Description
BaseLoadBalancer() Default constructor which sets name as "default", sets null ping, and RoundRobinRule as the rule.
BaseLoadBalancer(com.netflix.client.config.IClientConfig config)
BaseLoadBalancer(com.netflix.client.config.IClientConfig config, IRule rule, IPing ping)
BaseLoadBalancer(IPing ping, IRule rule)
BaseLoadBalancer(IPing ping, IRule rule, IPingStrategy pingStrategy)
BaseLoadBalancer(java.lang.String lbName, IRule rule, LoadBalancerStats lbStats)
BaseLoadBalancer(java.lang.String name, IRule rule, LoadBalancerStats stats, IPing ping)
BaseLoadBalancer(java.lang.String name, IRule rule, LoadBalancerStats stats, IPing ping, IPingStrategy pingStrategy)

Method Summary

Modifier and Type	Method and Description
void	addServer(Server newServer) Add a server to the 'allServer' list; does not verify uniqueness, so you could give a server a greater share by adding it more than once.
void	addServerListChangeListener(ServerListChangeListener listener)
void	addServers(java.util.List<Server> newServers) Add a list of servers to the 'allServer' list; does not verify uniqueness, so you could give a server a greater share by adding it more than once
void	addServerStatusChangeListener(ServerStatusChangeListener listener)
void	cancelPingTask()
java.lang.String	choose(java.lang.Object key)
Server	chooseServer(java.lang.Object key) Choose a server from load balancer.
void	forceQuickPing()
java.util.List<Server>	getAllServers()
com.netflix.client.config.IClientConfig	getClientConfig()
LoadBalancerStats	getLoadBalancerStats() Obtain LoadBalancer related Statistics
int	getMaxTotalPingTime()
java.lang.String	getName()
IPing	getPing()
int	getPingInterval()
PrimeConnections	getPrimeConnections()
java.util.List<Server>	getReachableServers()
IRule	getRule()
Server	getServerByIndex(int index, boolean availableOnly) return the server
int	getServerCount(boolean onlyAvailable) get the count of servers.
java.util.List<Server>	getServerList(AbstractLoadBalancer.ServerGroup serverGroup) List of servers that this Loadbalancer knows about
java.util.List<Server>	getServerList(boolean availableOnly)
protected void	init() Register with monitors and start priming connections if it is set.
void	initWithNiwsConfig(com.netflix.client.config.IClientConfig clientConfig)
void	initWithNiwsConfig(com.netflix.client.config.IClientConfig clientConfig, com.netflix.client.IClientConfigAware.Factory factory)
boolean	isEnablePrimingConnections()
boolean	isPingInProgress()
java.util.concurrent.locks.Lock	lockAllServerList(boolean write)
java.util.concurrent.locks.Lock	lockUpServerList(boolean write)
void	markServerDown(Server server) To be called by the clients of the load balancer to notify that a Server is down else, the LB will think its still Alive until the next Ping cycle - potentially (assuming that the LB Impl does a ping)
void	markServerDown(java.lang.String id)
void	primeCompleted(Server s, java.lang.Throwable lastException)
void	removeServerListChangeListener(ServerListChangeListener listener)
void	removeServerStatusChangeListener(ServerStatusChangeListener listener)
void	setEnablePrimingConnections(boolean enablePrimingConnections)
void	setLoadBalancerStats(LoadBalancerStats lbStats)
void	setMaxTotalPingTime(int maxTotalPingTimeSeconds)
void	setPing(IPing ping)
void	setPingInterval(int pingIntervalSeconds)
void	setPrimeConnections(PrimeConnections primeConnections)
void	setRule(IRule rule)
void	setServersList(java.util.List lsrv) Set the list of servers used as the server pool.
void	shutdown()
java.lang.String	toString()

Methods inherited from class com.netflix.loadbalancer.AbstractLoadBalancer

chooseServer

Methods inherited from class java.lang.Object

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

Field Detail

rule

protected IRule rule

pingStrategy

protected IPingStrategy pingStrategy

ping

protected IPing ping

allServerList

@Monitor(name="LoadBalancer_AllServerList",
         type=INFORMATIONAL)
protected volatile java.util.List<Server> allServerList

upServerList

@Monitor(name="LoadBalancer_UpServerList",
         type=INFORMATIONAL)
protected volatile java.util.List<Server> upServerList

allServerLock

protected java.util.concurrent.locks.ReadWriteLock allServerLock

upServerLock

protected java.util.concurrent.locks.ReadWriteLock upServerLock

name

protected java.lang.String name

lbTimer

protected java.util.Timer lbTimer

pingIntervalSeconds

protected int pingIntervalSeconds

maxTotalPingTimeSeconds

protected int maxTotalPingTimeSeconds

serverComparator

protected java.util.Comparator<Server> serverComparator

pingInProgress

protected java.util.concurrent.atomic.AtomicBoolean pingInProgress

lbStats

protected LoadBalancerStats lbStats

Constructor Detail

BaseLoadBalancer

public BaseLoadBalancer()

Default constructor which sets name as "default", sets null ping, and RoundRobinRule as the rule.

This constructor is mainly used by ClientFactory. Calling this constructor must be followed by calling init() or initWithNiwsConfig(IClientConfig) to complete initialization. This constructor is provided for reflection. When constructing programatically, it is recommended to use other constructors.

BaseLoadBalancer

public BaseLoadBalancer(java.lang.String lbName,
                        IRule rule,
                        LoadBalancerStats lbStats)

BaseLoadBalancer

public BaseLoadBalancer(IPing ping,
                        IRule rule)

BaseLoadBalancer

public BaseLoadBalancer(IPing ping,
                        IRule rule,
                        IPingStrategy pingStrategy)

BaseLoadBalancer

public BaseLoadBalancer(java.lang.String name,
                        IRule rule,
                        LoadBalancerStats stats,
                        IPing ping)

BaseLoadBalancer

public BaseLoadBalancer(java.lang.String name,
                        IRule rule,
                        LoadBalancerStats stats,
                        IPing ping,
                        IPingStrategy pingStrategy)

BaseLoadBalancer

public BaseLoadBalancer(com.netflix.client.config.IClientConfig config)

BaseLoadBalancer

public BaseLoadBalancer(com.netflix.client.config.IClientConfig config,
                        IRule rule,
                        IPing ping)

Method Detail

initWithNiwsConfig

public void initWithNiwsConfig(com.netflix.client.config.IClientConfig clientConfig)

Specified by:

initWithNiwsConfig in interface com.netflix.client.IClientConfigAware

initWithNiwsConfig

public void initWithNiwsConfig(com.netflix.client.config.IClientConfig clientConfig,
                               com.netflix.client.IClientConfigAware.Factory factory)

Specified by:

initWithNiwsConfig in interface com.netflix.client.IClientConfigAware

addServerListChangeListener

public void addServerListChangeListener(ServerListChangeListener listener)

removeServerListChangeListener

public void removeServerListChangeListener(ServerListChangeListener listener)

addServerStatusChangeListener

public void addServerStatusChangeListener(ServerStatusChangeListener listener)

removeServerStatusChangeListener

public void removeServerStatusChangeListener(ServerStatusChangeListener listener)

getClientConfig

public com.netflix.client.config.IClientConfig getClientConfig()

getName

public java.lang.String getName()

getLoadBalancerStats

public LoadBalancerStats getLoadBalancerStats()

Description copied from class: AbstractLoadBalancer

Obtain LoadBalancer related Statistics

Specified by:

getLoadBalancerStats in class AbstractLoadBalancer

setLoadBalancerStats

public void setLoadBalancerStats(LoadBalancerStats lbStats)

lockAllServerList

public java.util.concurrent.locks.Lock lockAllServerList(boolean write)

lockUpServerList

public java.util.concurrent.locks.Lock lockUpServerList(boolean write)

setPingInterval

public void setPingInterval(int pingIntervalSeconds)

getPingInterval

public int getPingInterval()

setMaxTotalPingTime

public void setMaxTotalPingTime(int maxTotalPingTimeSeconds)

getMaxTotalPingTime

public int getMaxTotalPingTime()

getPing

public IPing getPing()

getRule

public IRule getRule()

isPingInProgress

public boolean isPingInProgress()

setPing

public void setPing(IPing ping)

setRule

public void setRule(IRule rule)

getServerCount

public int getServerCount(boolean onlyAvailable)

get the count of servers.

Parameters:

onlyAvailable - if true, return only up servers.

addServer

public void addServer(Server newServer)

Add a server to the 'allServer' list; does not verify uniqueness, so you could give a server a greater share by adding it more than once.

addServers

public void addServers(java.util.List<Server> newServers)

Add a list of servers to the 'allServer' list; does not verify uniqueness, so you could give a server a greater share by adding it more than once

Specified by:

addServers in interface ILoadBalancer

Parameters:

newServers - new servers to add

setServersList

public void setServersList(java.util.List lsrv)

Set the list of servers used as the server pool. This overrides existing server list.

getServerByIndex

public Server getServerByIndex(int index,
                               boolean availableOnly)

return the server

Parameters:

index -

availableOnly -

getServerList

public java.util.List<Server> getServerList(boolean availableOnly)

Specified by:

getServerList in interface ILoadBalancer

Parameters:

availableOnly - if true, only live and available servers should be returned

getReachableServers

public java.util.List<Server> getReachableServers()

Specified by:

getReachableServers in interface ILoadBalancer

Returns:

Only the servers that are up and reachable.

getAllServers

public java.util.List<Server> getAllServers()

Specified by:

getAllServers in interface ILoadBalancer

Returns:

All known servers, both reachable and unreachable.

getServerList

public java.util.List<Server> getServerList(AbstractLoadBalancer.ServerGroup serverGroup)

Description copied from class: AbstractLoadBalancer

List of servers that this Loadbalancer knows about

Specified by:

getServerList in class AbstractLoadBalancer

Parameters:

serverGroup - Servers grouped by status, e.g., AbstractLoadBalancer.ServerGroup.STATUS_UP

cancelPingTask

public void cancelPingTask()

chooseServer

public Server chooseServer(java.lang.Object key)

Description copied from interface: ILoadBalancer

Choose a server from load balancer.

Specified by:

chooseServer in interface ILoadBalancer

Parameters:

key - An object that the load balancer may use to determine which server to return. null if the load balancer does not use this parameter.

Returns:

server chosen

choose

public java.lang.String choose(java.lang.Object key)

markServerDown

public void markServerDown(Server server)

Description copied from interface: ILoadBalancer

To be called by the clients of the load balancer to notify that a Server is down else, the LB will think its still Alive until the next Ping cycle - potentially (assuming that the LB Impl does a ping)

Specified by:

markServerDown in interface ILoadBalancer

Parameters:

server - Server to mark as down

markServerDown

public void markServerDown(java.lang.String id)

forceQuickPing

public void forceQuickPing()

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

init

protected void init()

Register with monitors and start priming connections if it is set.

getPrimeConnections

public final PrimeConnections getPrimeConnections()

setPrimeConnections

public final void setPrimeConnections(PrimeConnections primeConnections)

primeCompleted

public void primeCompleted(Server s,
                           java.lang.Throwable lastException)

Specified by:

primeCompleted in interface PrimeConnections.PrimeConnectionListener

isEnablePrimingConnections

public boolean isEnablePrimingConnections()

setEnablePrimingConnections

public final void setEnablePrimingConnections(boolean enablePrimingConnections)

shutdown

public void shutdown()