Package org.apache.hadoop.tools.fedbalance.procedure

Class BalanceProcedureScheduler

java.lang.Object

org.apache.hadoop.tools.fedbalance.procedure.BalanceProcedureScheduler

public class BalanceProcedureScheduler
extends java.lang.Object

 The state machine framework consist of:
   Job:                The state machine. It implements the basic logic of the
                       state machine.
   Procedure:          The components of the job. It implements the custom
                       logic.
   ProcedureScheduler: The multi-thread model responsible for running,
                       recovering, handling errors and job persistence.
   Journal:            It handles the job persistence and recover.

 Example:
   Job.Builder builder = new Job.Builder<>();
   builder.nextProcedure(new WaitProcedure("wait", 1000, 30 * 1000));
   Job job = builder.build();

   ProcedureScheduler scheduler = new ProcedureScheduler(CONF);
   scheduler.init();
   scheduler.submit(job);
   scheduler.waitUntilDone(job);
 

Field Summary

Fields

Modifier and Type	Field	Description
static org.slf4j.Logger	LOG

Constructor Summary

Constructors

Constructor	Description
BalanceProcedureScheduler(org.apache.hadoop.conf.Configuration conf)

Method Summary

Modifier and Type	Method	Description
BalanceJob	findJob(BalanceJob job)	Find job in scheduler.
java.util.Collection<BalanceJob>	getAllJobs()	Return all jobs in the scheduler.
void	init(boolean recoverJobs)	Init the scheduler.
boolean	isRunning()	The running state of the scheduler.
BalanceJob	remove(BalanceJob job)	Remove the job from scheduler if it finishes.
void	setJournal(BalanceJournal journal)
void	shutDown()	Shutdown the scheduler.
void	shutDownAndWait(int timeout)	Shutdown scheduler and wait at most timeout seconds for procedures to finish.
void	submit(BalanceJob job)	Submit the job.
void	waitUntilDone(BalanceJob job)	Wait permanently until the job is done.

Methods inherited from class java.lang.Object

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

Field Detail

LOG

public static final org.slf4j.Logger LOG

Constructor Detail

BalanceProcedureScheduler

public BalanceProcedureScheduler(org.apache.hadoop.conf.Configuration conf)

Method Detail

init

public void init(boolean recoverJobs)
          throws java.io.IOException

Init the scheduler.

Parameters:

recoverJobs - whether to recover all the jobs from journal or not.

Throws:

java.io.IOException

submit

public void submit(BalanceJob job)
            throws java.io.IOException

Submit the job.

Throws:

java.io.IOException

remove

public BalanceJob remove(BalanceJob job)

Remove the job from scheduler if it finishes.

findJob

public BalanceJob findJob(BalanceJob job)

Find job in scheduler.

Returns:

the job in scheduler. Null if the schedule has no job with the same id.

getAllJobs

public java.util.Collection<BalanceJob> getAllJobs()

Return all jobs in the scheduler.

waitUntilDone

public void waitUntilDone(BalanceJob job)

Wait permanently until the job is done.

isRunning

public boolean isRunning()

The running state of the scheduler.

shutDown

public void shutDown()

Shutdown the scheduler.

shutDownAndWait

public void shutDownAndWait(int timeout)

Shutdown scheduler and wait at most timeout seconds for procedures to finish.

Parameters:

timeout - Wait at most timeout seconds for procedures to finish.

setJournal

@VisibleForTesting
public void setJournal(BalanceJournal journal)