Package org.apache.hadoop.ha.protocolPB

Class HAServiceProtocolClientSideTranslatorPB

java.lang.Object

org.apache.hadoop.ha.protocolPB.HAServiceProtocolClientSideTranslatorPB

All Implemented Interfaces:

Closeable, AutoCloseable, HAServiceProtocol, ProtocolTranslator

@Private
@Stable
public class HAServiceProtocolClientSideTranslatorPB
extends Object
implements HAServiceProtocol, Closeable, ProtocolTranslator

This class is the client side translator to translate the requests made on HAServiceProtocol interfaces to the RPC server implementing HAServiceProtocolPB.

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.hadoop.ha.HAServiceProtocol

HAServiceProtocol.HAServiceState, HAServiceProtocol.RequestSource, HAServiceProtocol.StateChangeRequestInfo

Field Summary

Fields inherited from interface org.apache.hadoop.ha.HAServiceProtocol

versionID

Constructor Summary

Constructors

Constructor	Description
HAServiceProtocolClientSideTranslatorPB(InetSocketAddress addr, Configuration conf)
HAServiceProtocolClientSideTranslatorPB(InetSocketAddress addr, Configuration conf, SocketFactory socketFactory, int timeout)

Method Summary

Modifier and Type	Method	Description
void	close()
HAServiceStatus	getServiceStatus()	Return the current status of the service.
Object	getUnderlyingProxyObject()	Return the proxy object underlying this protocol translator.
void	monitorHealth()	Monitor the health of service.
void	transitionToActive(HAServiceProtocol.StateChangeRequestInfo reqInfo)	Request service to transition to active state.
void	transitionToObserver(HAServiceProtocol.StateChangeRequestInfo reqInfo)	Request service to transition to observer state.
void	transitionToStandby(HAServiceProtocol.StateChangeRequestInfo reqInfo)	Request service to transition to standby state.

Methods inherited from class java.lang.Object

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

Constructor Details

HAServiceProtocolClientSideTranslatorPB

public HAServiceProtocolClientSideTranslatorPB(InetSocketAddress addr,
 Configuration conf)
                                        throws IOException

Throws:

IOException

HAServiceProtocolClientSideTranslatorPB

public HAServiceProtocolClientSideTranslatorPB(InetSocketAddress addr,
 Configuration conf,
 SocketFactory socketFactory,
 int timeout)
                                        throws IOException

Throws:

IOException

Method Details

monitorHealth

public void monitorHealth()
                   throws IOException

Description copied from interface: HAServiceProtocol

Monitor the health of service. This periodically called by the HA frameworks to monitor the health of the service. Service is expected to perform checks to ensure it is functional. If the service is not healthy due to failure or partial failure, it is expected to throw HealthCheckFailedException. The definition of service not healthy is left to the service. Note that when health check of an Active service fails, failover to standby may be done.

Specified by:

monitorHealth in interface HAServiceProtocol

Throws:

HealthCheckFailedException - if the health check of a service fails.

AccessControlException - if access is denied.

IOException - if other errors happen

transitionToActive

public void transitionToActive(HAServiceProtocol.StateChangeRequestInfo reqInfo)
                        throws IOException

Description copied from interface: HAServiceProtocol

Request service to transition to active state. No operation, if the service is already in active state.

Specified by:

transitionToActive in interface HAServiceProtocol

Parameters:

reqInfo - reqInfo.

Throws:

ServiceFailedException - if transition from standby to active fails.

AccessControlException - if access is denied.

IOException - if other errors happen

transitionToStandby

public void transitionToStandby(HAServiceProtocol.StateChangeRequestInfo reqInfo)
                         throws IOException

Description copied from interface: HAServiceProtocol

Request service to transition to standby state. No operation, if the service is already in standby state.

Specified by:

transitionToStandby in interface HAServiceProtocol

Parameters:

reqInfo - reqInfo.

Throws:

ServiceFailedException - if transition from active to standby fails.

AccessControlException - if access is denied.

IOException - if other errors happen

transitionToObserver

public void transitionToObserver(HAServiceProtocol.StateChangeRequestInfo reqInfo)
                          throws IOException

Description copied from interface: HAServiceProtocol

Request service to transition to observer state. No operation, if the service is already in observer state.

Specified by:

transitionToObserver in interface HAServiceProtocol

Parameters:

reqInfo - reqInfo.

Throws:

ServiceFailedException - if transition from standby to observer fails.

AccessControlException - if access is denied.

IOException - if other errors happen

getServiceStatus

public HAServiceStatus getServiceStatus()
                                 throws IOException

Description copied from interface: HAServiceProtocol

Return the current status of the service. The status indicates the current state (e.g ACTIVE/STANDBY) as well as some additional information.

Specified by:

getServiceStatus in interface HAServiceProtocol

Returns:

HAServiceStatus.

Throws:

AccessControlException - if access is denied.

IOException - if other errors happen

See Also:

• HAServiceStatus

close

public void close()

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

getUnderlyingProxyObject

public Object getUnderlyingProxyObject()

Description copied from interface: ProtocolTranslator

Return the proxy object underlying this protocol translator.

Specified by:

getUnderlyingProxyObject in interface ProtocolTranslator

Returns:

the proxy object underlying this protocol translator.