Package org.apache.hadoop.hdfs.server.federation.router

Class ConnectionManager

java.lang.Object

org.apache.hadoop.hdfs.server.federation.router.ConnectionManager

public class ConnectionManager
extends java.lang.Object

Implements a pool of connections for the Router to be able to open many connections to many Namenodes.

Constructor Summary

Constructors

Constructor	Description
ConnectionManager(org.apache.hadoop.conf.Configuration config)
ConnectionManager(org.apache.hadoop.conf.Configuration config, org.apache.hadoop.hdfs.server.federation.router.RouterStateIdContext routerStateIdContext)	Creates a proxy client connection pool manager.

Method Summary

Modifier and Type	Method	Description
void	close()	Stop the connection manager by closing all the pools.
ConnectionContext	getConnection(org.apache.hadoop.security.UserGroupInformation ugi, java.lang.String nnAddress, java.lang.Class<?> protocol, java.lang.String nsId)	Fetches the next available proxy client in the pool.
java.lang.String	getJSON()	Get a JSON representation of the connection pool.
int	getNumActiveConnections()	Get number of active connections.
int	getNumActiveConnectionsRecently()	Get number of recently active connections.
int	getNumConnectionPools()	Get the number of connection pools.
int	getNumConnections()	Get number of open connections.
int	getNumCreatingConnections()	Get the number of connections to be created.
int	getNumIdleConnections()	Get number of idle connections.
void	start()	Start the connection manager.

Methods inherited from class java.lang.Object

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

Constructor Detail

ConnectionManager

public ConnectionManager(org.apache.hadoop.conf.Configuration config)

ConnectionManager

public ConnectionManager(org.apache.hadoop.conf.Configuration config,
                         org.apache.hadoop.hdfs.server.federation.router.RouterStateIdContext routerStateIdContext)

Creates a proxy client connection pool manager.

Parameters:

config - Configuration for the connections.

routerStateIdContext - Federated namespace context for router.

Method Detail

start

public void start()

Start the connection manager.

close

public void close()

Stop the connection manager by closing all the pools.

getConnection

public ConnectionContext getConnection(org.apache.hadoop.security.UserGroupInformation ugi,
                                       java.lang.String nnAddress,
                                       java.lang.Class<?> protocol,
                                       java.lang.String nsId)
                                throws java.io.IOException

Fetches the next available proxy client in the pool. Each client connection is reserved for a single user and cannot be reused until free.

Parameters:

ugi - User group information.

nnAddress - Namenode address for the connection.

protocol - Protocol for the connection.

nsId - Nameservice identity.

Returns:

Proxy client to connect to nnId as UGI.

Throws:

java.io.IOException - If the connection cannot be obtained.

getNumConnectionPools

public int getNumConnectionPools()

Get the number of connection pools.

Returns:

Number of connection pools.

getNumConnections

public int getNumConnections()

Get number of open connections.

Returns:

Number of open connections.

getNumActiveConnections

public int getNumActiveConnections()

Get number of active connections.

Returns:

Number of active connections.

getNumIdleConnections

public int getNumIdleConnections()

Get number of idle connections.

Returns:

Number of active connections.

getNumActiveConnectionsRecently

public int getNumActiveConnectionsRecently()

Get number of recently active connections.

Returns:

Number of recently active connections.

getNumCreatingConnections

public int getNumCreatingConnections()

Get the number of connections to be created.

Returns:

Number of connections to be created.

getJSON

public java.lang.String getJSON()

Get a JSON representation of the connection pool.

Returns:

JSON representation of all the connection pools.