org.apache.hadoop.hdfs.server.namenode.ha

Class ConfiguredFailoverProxyProvider<T>

java.lang.Object

org.apache.hadoop.hdfs.server.namenode.ha.AbstractNNFailoverProxyProvider<T>

org.apache.hadoop.hdfs.server.namenode.ha.ConfiguredFailoverProxyProvider<T>

All Implemented Interfaces:

Closeable, AutoCloseable, org.apache.hadoop.io.retry.FailoverProxyProvider<T>

Direct Known Subclasses:

RequestHedgingProxyProvider

public class ConfiguredFailoverProxyProvider<T>
extends AbstractNNFailoverProxyProvider<T>

A FailoverProxyProvider implementation which allows one to configure multiple URIs to connect to during fail-over. A random configured address is tried first, and on a fail-over event the other addresses are tried sequentially in a random order.

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.hadoop.hdfs.server.namenode.ha.AbstractNNFailoverProxyProvider

AbstractNNFailoverProxyProvider.NNProxyInfo<T>

Nested classes/interfaces inherited from interface org.apache.hadoop.io.retry.FailoverProxyProvider

org.apache.hadoop.io.retry.FailoverProxyProvider.ProxyInfo<T>

Field Summary

Fields

Modifier and Type	Field and Description
protected List<AbstractNNFailoverProxyProvider.NNProxyInfo<T>>	proxies

Fields inherited from class org.apache.hadoop.hdfs.server.namenode.ha.AbstractNNFailoverProxyProvider

conf, factory, fallbackToSimpleAuth, LOG, ugi, xface

Constructor Summary

Constructors

Constructor and Description
ConfiguredFailoverProxyProvider(org.apache.hadoop.conf.Configuration conf, URI uri, Class<T> xface, org.apache.hadoop.hdfs.server.namenode.ha.HAProxyFactory<T> factory)

Method Summary

Methods

Modifier and Type	Method and Description
void	close() Close all the proxy objects which have been opened over the lifetime of this proxy provider.
org.apache.hadoop.io.retry.FailoverProxyProvider.ProxyInfo<T>	getProxy() Lazily initialize the RPC proxy object.
void	performFailover(T currentProxy)
boolean	useLogicalURI() Logical URI is required for this failover proxy provider.

Methods inherited from class org.apache.hadoop.hdfs.server.namenode.ha.AbstractNNFailoverProxyProvider

createProxyIfNeeded, getFallbackToSimpleAuth, getInterface, getProxyAddresses, getRandomOrder, setFallbackToSimpleAuth

Methods inherited from class java.lang.Object

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

Field Detail

proxies

protected final List<AbstractNNFailoverProxyProvider.NNProxyInfo<T>> proxies

Constructor Detail

ConfiguredFailoverProxyProvider

public ConfiguredFailoverProxyProvider(org.apache.hadoop.conf.Configuration conf,
                               URI uri,
                               Class<T> xface,
                               org.apache.hadoop.hdfs.server.namenode.ha.HAProxyFactory<T> factory)

Method Detail

getProxy

public org.apache.hadoop.io.retry.FailoverProxyProvider.ProxyInfo<T> getProxy()

Lazily initialize the RPC proxy object.

performFailover

public void performFailover(T currentProxy)

close

public void close()
           throws IOException

Close all the proxy objects which have been opened over the lifetime of this proxy provider.

Throws:

IOException

useLogicalURI

public boolean useLogicalURI()

Logical URI is required for this failover proxy provider.

Specified by:

useLogicalURI in class AbstractNNFailoverProxyProvider<T>

Returns:

true if logical HA URI is used. false, if not used.