org.apache.hadoop.yarn.applications.distributedshell

クラス Client

java.lang.Object

org.apache.hadoop.yarn.applications.distributedshell.Client

@InterfaceAudience.Public
 @InterfaceStability.Unstable
public class Client
extends Object

Client for Distributed Shell application submission to YARN.

The distributed shell client allows an application master to be launched that in turn would run the provided shell command on a set of containers.

This client is meant to act as an example on how to write yarn-based applications.

To submit an application, a client first needs to connect to the ResourceManager aka ApplicationsManager or ASM via the ApplicationClientProtocol. The ApplicationClientProtocol provides a way for the client to get access to cluster information and to request for a new ApplicationId.

For the actual job submission, the client first has to create an ApplicationSubmissionContext. The ApplicationSubmissionContext defines the application details such as ApplicationId and application name, the priority assigned to the application and the queue to which this application needs to be assigned. In addition to this, the ApplicationSubmissionContext also defines the ContainerLaunchContext which describes the Container with which the ApplicationMaster is launched.

The ContainerLaunchContext in this scenario defines the resources to be allocated for the ApplicationMaster's container, the local resources (jars, configuration files) to be made available and the environment to be set for the ApplicationMaster and the commands to be executed to run the ApplicationMaster.

Using the ApplicationSubmissionContext, the client submits the application to the ResourceManager and then monitors the application by requesting the ResourceManager for an ApplicationReport at regular time intervals. In case of the application taking too long, the client kills the application by submitting a KillApplicationRequest to the ResourceManager.

フィールドのサマリー

フィールド

修飾子とタイプ	フィールドと説明
static String	SCRIPT_PATH

コンストラクタのサマリー

コンストラクタ

コンストラクタと説明
Client()
Client(Configuration conf)

メソッドのサマリー

修飾子とタイプ	メソッドと説明
boolean	init(String[] args) Parse command line options
static void	main(String[] args)
boolean	run() Main run function for the client

クラスから継承されたメソッド java.lang.Object

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

フィールドの詳細

SCRIPT_PATH

public static final String SCRIPT_PATH

関連項目:

定数フィールド値

コンストラクタの詳細

Client

public Client(Configuration conf)
       throws Exception

例外:

Exception

Client

public Client()
       throws Exception

例外:

Exception

メソッドの詳細

main

public static void main(String[] args)

パラメータ:

args - Command line arguments

init

public boolean init(String[] args)
             throws org.apache.commons.cli.ParseException

Parse command line options

パラメータ:

args - Parsed command line options

戻り値:

Whether the init was successful to run the client

例外:

org.apache.commons.cli.ParseException

run

public boolean run()
            throws IOException,
                   YarnException

Main run function for the client

戻り値:

true if application completed successfully

例外:

IOException

YarnException