Package org.apache.hadoop.yarn.server.nodemanager.health

Class NodeHealthCheckerService

java.lang.Object

org.apache.hadoop.service.AbstractService

org.apache.hadoop.service.CompositeService

org.apache.hadoop.yarn.server.nodemanager.health.NodeHealthCheckerService

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable, org.apache.hadoop.service.Service, HealthReporter

public class NodeHealthCheckerService
extends org.apache.hadoop.service.CompositeService
implements HealthReporter

This class provides functionality of checking the health of a node and reporting back to the service for which the health checker has been asked to report. It is a CompositeService: every Service must be registered first in serviceInit, and should also implement the HealthReporter interface - otherwise an exception is thrown. Calling functions of HealthReporter merge its dependent services' reports.

See Also:

HealthReporter, LocalDirsHandlerService, TimedHealthReporterService

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.hadoop.service.CompositeService

org.apache.hadoop.service.CompositeService.CompositeServiceShutdownHook

Nested classes/interfaces inherited from interface org.apache.hadoop.service.Service

org.apache.hadoop.service.Service.STATE

Field Summary

Fields

Modifier and Type	Field	Description
static org.slf4j.Logger	LOG
static java.lang.String	SEPARATOR

Fields inherited from class org.apache.hadoop.service.CompositeService

STOP_ONLY_STARTED_SERVICES

Constructor Summary

Constructors

Constructor	Description
NodeHealthCheckerService(LocalDirsHandlerService dirHandlerService)

Method Summary

Modifier and Type	Method	Description
LocalDirsHandlerService	getDiskHandler()
java.lang.String	getHealthReport()	Joining the health reports of the dependent services.
long	getLastHealthReportTime()	Returns time stamp when node health check was last run.
boolean	isHealthy()	Gets whether the node is healthy or not.
void	reportException(java.lang.Exception exception)	Propagating an exception to ExceptionReporter.
protected void	serviceInit(org.apache.hadoop.conf.Configuration conf)

Methods inherited from class org.apache.hadoop.service.CompositeService

addIfService, addService, getServices, removeService, serviceStart, serviceStop

Methods inherited from class org.apache.hadoop.service.AbstractService

close, getBlockers, getConfig, getFailureCause, getFailureState, getLifecycleHistory, getName, getServiceState, getStartTime, init, isInState, noteFailure, putBlocker, registerGlobalListener, registerServiceListener, removeBlocker, setConfig, start, stop, toString, unregisterGlobalListener, unregisterServiceListener, waitForServiceToStop

Methods inherited from class java.lang.Object

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

Field Detail

LOG

public static final org.slf4j.Logger LOG

SEPARATOR

public static final java.lang.String SEPARATOR

See Also:

Constant Field Values

Constructor Detail

NodeHealthCheckerService

public NodeHealthCheckerService(LocalDirsHandlerService dirHandlerService)

Method Detail

serviceInit

protected void serviceInit(org.apache.hadoop.conf.Configuration conf)
                    throws java.lang.Exception

Overrides:

serviceInit in class org.apache.hadoop.service.CompositeService

Throws:

java.lang.Exception

getHealthReport

public java.lang.String getHealthReport()

Joining the health reports of the dependent services.

Specified by:

getHealthReport in interface HealthReporter

Returns:

the report string about the health of the node

isHealthy

public boolean isHealthy()

Description copied from interface: HealthReporter

Gets whether the node is healthy or not.

Specified by:

isHealthy in interface HealthReporter

Returns:

true if the node is healthy

getLastHealthReportTime

public long getLastHealthReportTime()

Description copied from interface: HealthReporter

Returns time stamp when node health check was last run.

Specified by:

getLastHealthReportTime in interface HealthReporter

Returns:

when the last time the node health status is reported

getDiskHandler

public LocalDirsHandlerService getDiskHandler()

Returns:

the disk handler

reportException

public void reportException(java.lang.Exception exception)

Propagating an exception to ExceptionReporter.

Parameters:

exception - the exception to propagate