org.apache.hadoop.yarn.server.sharedcachemanager

Class AppChecker

java.lang.Object

org.apache.hadoop.service.AbstractService

org.apache.hadoop.service.CompositeService

org.apache.hadoop.yarn.server.sharedcachemanager.AppChecker

All Implemented Interfaces:

Closeable, AutoCloseable, org.apache.hadoop.service.Service

Direct Known Subclasses:

RemoteAppChecker

@InterfaceAudience.Private
@InterfaceStability.Evolving
public abstract class AppChecker
extends org.apache.hadoop.service.CompositeService

An interface for checking whether an app is running so that the cleaner service may determine if it can safely remove a cached entry.

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

STOP_ONLY_STARTED_SERVICES

Constructor Summary

Constructors

Constructor and Description
AppChecker()
AppChecker(String name)

Method Summary

Methods

Modifier and Type	Method and Description
abstract Collection<org.apache.hadoop.yarn.api.records.ApplicationId>	getActiveApplications() Returns the list of all active apps at the given time.
abstract boolean	isApplicationActive(org.apache.hadoop.yarn.api.records.ApplicationId id) Returns whether the app is in an active state.

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

addIfService, addService, getServices, removeService, serviceInit, 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

Constructor Detail

AppChecker

public AppChecker()

AppChecker

public AppChecker(String name)

Method Detail

isApplicationActive

@InterfaceAudience.Private
public abstract boolean isApplicationActive(org.apache.hadoop.yarn.api.records.ApplicationId id)
                                     throws org.apache.hadoop.yarn.exceptions.YarnException

Returns whether the app is in an active state.

Returns:

true if the app is found and is not in one of the completed states; false otherwise

Throws:

org.apache.hadoop.yarn.exceptions.YarnException - if there is an error in determining the app state

getActiveApplications

@InterfaceAudience.Private
public abstract Collection<org.apache.hadoop.yarn.api.records.ApplicationId> getActiveApplications()
                                                                                            throws org.apache.hadoop.yarn.exceptions.YarnException

Returns the list of all active apps at the given time.

Returns:

the list of active apps, or an empty list if there is none

Throws:

org.apache.hadoop.yarn.exceptions.YarnException - if there is an error in obtaining the list