org.apache.twill.internal

Class BasicTwillContext

java.lang.Object

org.apache.twill.internal.BasicTwillContext

All Implemented Interfaces:

ServiceAnnouncer, TwillContext, DiscoveryServiceClient

public final class BasicTwillContext
extends Object
implements TwillContext

Implementation of TwillContext that provides the basic runtime information of a TwillRunnable.

Constructor Summary

Constructors

Constructor and Description
BasicTwillContext(RunId runId, RunId appRunId, InetAddress host, String[] args, String[] appArgs, TwillRunnableSpecification spec, int instanceId, DiscoveryService discoveryService, DiscoveryServiceClient discoveryServiceClient, ZKClient zkClient, int instanceCount, int allowedMemoryMB, int virtualCores)

Method Summary

Modifier and Type	Method and Description
Cancellable	announce(String serviceName, int port) Registers an endpoint that could be discovered by external party.
Cancellable	announce(String serviceName, int port, byte[] payload) Registers an endpoint that could be discovered by external party with a payload.
Lock	createLock(String name) Creates a Lock for performing locking mechanism within the same TwillApplication.
ServiceDiscovered	discover(String name) Discover service with the given name that is announced within the same TwillApplication.
Cancellable	electLeader(String name, ElectionHandler participantHandler) Register to participate in a leader election by instances within the same TwillApplication.
String[]	getApplicationArguments() Returns the runtime arguments that are passed to the TwillApplication.
RunId	getApplicationRunId() Returns the RunId of this running application.
String[]	getArguments() Returns the runtime arguments that are passed to the TwillRunnable.
InetAddress	getHost() Returns the hostname that the runnable is running on.
int	getInstanceCount() Returns the number of running instances assigned for this TwillRunnable.
int	getInstanceId() Returns an integer id from 0 to (instanceCount - 1).
int	getMaxMemoryMB() Returns the amount of memory in MB the runnable is allowed to use.
RunId	getRunId() Returns the RunId of this running instance of TwillRunnable.
TwillRunnableSpecification	getSpecification() Returns the TwillRunnableSpecification that was created by TwillRunnable.configure().
int	getVirtualCores() Returns the number of virtual cores the runnable is allowed to use.
void	setInstanceCount(int count)
void	stop() Stops and frees any currently allocated resources.

Methods inherited from class java.lang.Object

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

Constructor Detail

BasicTwillContext

public BasicTwillContext(RunId runId,
                         RunId appRunId,
                         InetAddress host,
                         String[] args,
                         String[] appArgs,
                         TwillRunnableSpecification spec,
                         int instanceId,
                         DiscoveryService discoveryService,
                         DiscoveryServiceClient discoveryServiceClient,
                         ZKClient zkClient,
                         int instanceCount,
                         int allowedMemoryMB,
                         int virtualCores)

Method Detail

getRunId

public RunId getRunId()

Description copied from interface: TwillContext

Returns the RunId of this running instance of TwillRunnable.

Specified by:

getRunId in interface TwillContext

getApplicationRunId

public RunId getApplicationRunId()

Description copied from interface: TwillContext

Returns the RunId of this running application.

Specified by:

getApplicationRunId in interface TwillContext

getInstanceCount

public int getInstanceCount()

Description copied from interface: TwillContext

Returns the number of running instances assigned for this TwillRunnable.

Specified by:

getInstanceCount in interface TwillContext

setInstanceCount

public void setInstanceCount(int count)

getHost

public InetAddress getHost()

Description copied from interface: TwillContext

Returns the hostname that the runnable is running on.

Specified by:

getHost in interface TwillContext

getArguments

public String[] getArguments()

Description copied from interface: TwillContext

Returns the runtime arguments that are passed to the TwillRunnable.

Specified by:

getArguments in interface TwillContext

getApplicationArguments

public String[] getApplicationArguments()

Description copied from interface: TwillContext

Returns the runtime arguments that are passed to the TwillApplication.

Specified by:

getApplicationArguments in interface TwillContext

getSpecification

public TwillRunnableSpecification getSpecification()

Description copied from interface: TwillContext

Returns the TwillRunnableSpecification that was created by TwillRunnable.configure().

Specified by:

getSpecification in interface TwillContext

getInstanceId

public int getInstanceId()

Description copied from interface: TwillContext

Returns an integer id from 0 to (instanceCount - 1).

Specified by:

getInstanceId in interface TwillContext

getVirtualCores

public int getVirtualCores()

Description copied from interface: TwillContext

Returns the number of virtual cores the runnable is allowed to use.

Specified by:

getVirtualCores in interface TwillContext

getMaxMemoryMB

public int getMaxMemoryMB()

Description copied from interface: TwillContext

Returns the amount of memory in MB the runnable is allowed to use.

Specified by:

getMaxMemoryMB in interface TwillContext

announce

public Cancellable announce(String serviceName,
                            int port)

Description copied from interface: ServiceAnnouncer

Registers an endpoint that could be discovered by external party.

Specified by:

announce in interface ServiceAnnouncer

Parameters:

serviceName - Name of the endpoint

port - Port of the endpoint

announce

public Cancellable announce(String serviceName,
                            int port,
                            byte[] payload)

Description copied from interface: ServiceAnnouncer

Registers an endpoint that could be discovered by external party with a payload.

Specified by:

announce in interface ServiceAnnouncer

Parameters:

serviceName - Name of the endpoint

port - Port of the endpoint

payload - byte array payload

discover

public ServiceDiscovered discover(String name)

Description copied from interface: TwillContext

Discover service with the given name that is announced within the same TwillApplication.

Specified by:

discover in interface TwillContext

Specified by:

discover in interface DiscoveryServiceClient

Parameters:

name - Name of the service

Returns:

A ServiceDiscovered object representing the result.

electLeader

public Cancellable electLeader(String name,
                               ElectionHandler participantHandler)

Description copied from interface: TwillContext

Register to participate in a leader election by instances within the same TwillApplication.

Specified by:

electLeader in interface TwillContext

Parameters:

name - Unique name for the election

Returns:

A Cancellable object representing this candidate's participation.

createLock

public Lock createLock(String name)

Description copied from interface: TwillContext

Creates a Lock for performing locking mechanism within the same TwillApplication. The lock created is a reentrant such that if the lock is owned by the current thread, it will return immediately.

Specified by:

createLock in interface TwillContext

Parameters:

name - Unique name for the lock

Returns:

A Lock object

stop

public void stop()

Stops and frees any currently allocated resources.