com.bigdata.service
Class MetadataService.NextPartitionIdTask

java.lang.Object
  com.bigdata.journal.AbstractTask
      com.bigdata.service.MetadataService.NextPartitionIdTask

All Implemented Interfaces:

ITask, Callable

Enclosing class:

MetadataService

protected static class MetadataService.NextPartitionIdTask
extends AbstractTask

Task assigns the next partition identifier for a registered scale-out index in a restart-safe manner.

Nested Class Summary

Nested classes/interfaces inherited from class com.bigdata.journal.AbstractTask

AbstractTask.DelegateTask<T>, AbstractTask.InnerReadWriteTxServiceCallable, AbstractTask.InnerWriteServiceCallable<T>, AbstractTask.ResubmitException

Field Summary

Fields inherited from class com.bigdata.journal.AbstractTask

checkpointNanoTime, concurrencyManager, DEBUG, INFO, isReadWriteTx, log, nanoTime_assignedWorker, nanoTime_beginWork, nanoTime_finishedWork, nanoTime_submitTask, readOnly, resourceManager, taskCounters, timestamp, transactionManager, tx

Constructor Summary

protected

MetadataService.NextPartitionIdTask(IConcurrencyManager concurrencyManager, String resource)

Method Summary

protected Object

doTask() Implement the task behavior here.

Methods inherited from class com.bigdata.journal.AbstractTask

assertResource, assertRunning, assertUnisolated, call, clearLoggingContext, dropIndex, getCommitTime, getIndex, getJournal, getOnlyResource, getResource, getResourceManager, getTaskCounters, getTaskName, getTimestamp, isResource, registerIndex, setupLoggingContext, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

MetadataService.NextPartitionIdTask

protected MetadataService.NextPartitionIdTask(IConcurrencyManager concurrencyManager,
                                              String resource)

Parameters:

concurrencyManager -

resource -

Method Detail

doTask

protected Object doTask()
                 throws Exception

Description copied from class: AbstractTask

Implement the task behavior here.

Note: Long-running implementations MUST periodically test Thread.interrupted() and MUST throw an exception, such as InterruptedException, if they are interrupted. This behavior allows tasks to be canceled in a timely manner.

If you ignore or fail to test Thread.interrupted() then your task CAN NOT be aborted. If it is Future.cancel(boolean) with false then the task will run to completion even though it has been cancelled (but the Future will appear to have been cancelled).

If you simply return rather than throwing an exception then the WriteExecutorService will assume that your task completed and your (partial) results will be made restart-safe at the next commit!

Specified by:

doTask in class AbstractTask

Returns:

The next partition identifier as an Integer.

Throws:

Exception - The exception that will be thrown by AbstractTask.call() iff the operation fails.

InterruptedException - This exception SHOULD be thrown if Thread.interrupted() becomes true during execution.