org.apache.zookeeper.client

Class StaticHostProvider

java.lang.Object

org.apache.zookeeper.client.StaticHostProvider

All Implemented Interfaces:

org.apache.zookeeper.client.HostProvider

@InterfaceAudience.Public
public final class StaticHostProvider
extends Object
implements org.apache.zookeeper.client.HostProvider

Most simple HostProvider, resolves on every next() call.

Please be aware that although this class doesn't do any DNS caching, there're multiple levels of caching already present across the stack like in JVM, OS level, hardware, etc. The best we could do here is to get the most recent address from the underlying system which is considered up-to-date.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	StaticHostProvider.Resolver

Constructor Summary

Constructors

Constructor and Description
StaticHostProvider(Collection<InetSocketAddress> serverAddresses) Constructs a SimpleHostSet.
StaticHostProvider(Collection<InetSocketAddress> serverAddresses, StaticHostProvider.Resolver resolver) Introduced for testing purposes.

Method Summary

Modifier and Type	Method and Description
InetSocketAddress	next(long spinDelay)
void	onConnected()
int	size()

Methods inherited from class java.lang.Object

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

Constructor Detail

StaticHostProvider

public StaticHostProvider(Collection<InetSocketAddress> serverAddresses)

Constructs a SimpleHostSet.

Parameters:

serverAddresses - possibly unresolved ZooKeeper server addresses

Throws:

IllegalArgumentException - if serverAddresses is empty or resolves to an empty list

StaticHostProvider

public StaticHostProvider(Collection<InetSocketAddress> serverAddresses,
                          StaticHostProvider.Resolver resolver)

Introduced for testing purposes. getAllByName() is a static method of InetAddress, therefore cannot be easily mocked. By abstraction of Resolver interface we can easily inject a mocked implementation in tests.

Parameters:

serverAddresses - possibly unresolved ZooKeeper server addresses

resolver - custom resolver implementation

Throws:

IllegalArgumentException - if serverAddresses is empty or resolves to an empty list

Method Detail

size

public int size()

Specified by:

size in interface org.apache.zookeeper.client.HostProvider

next

public InetSocketAddress next(long spinDelay)

Specified by:

next in interface org.apache.zookeeper.client.HostProvider

onConnected

public void onConnected()

Specified by:

onConnected in interface org.apache.zookeeper.client.HostProvider