org.apache.oozie.command
Class PurgeXCommand

java.lang.Object
  org.apache.oozie.command.XCommand<Void>
      org.apache.oozie.command.PurgeXCommand

All Implemented Interfaces:

Callable<Void>, XCallable<Void>

public class PurgeXCommand
extends XCommand<Void>

This class is used to purge workflows, coordinators, and bundles. It takes into account the relationships between workflows and coordinators, and coordinators and bundles. It also only acts on 'limit' number of items at a time to not overtax the DB and in case something gets rolled back. Also, children are always deleted before their parents in case of a rollback.

Field Summary

Fields inherited from class org.apache.oozie.command.XCommand

DEFAULT_LOCK_TIMEOUT, DEFAULT_REQUEUE_DELAY, dryrun, eventService, instrumentation, INSTRUMENTATION_GROUP, LOG, logInfo

Constructor Summary

PurgeXCommand(int wfOlderThan, int coordOlderThan, int bundleOlderThan, int limit)

Method Summary

protected Void	execute() Command execution body.
String	getEntityKey() Return the entity key for the command.
protected boolean	isLockRequired() Indicate if the the command requires locking.
protected void	loadState() Load the necessary state to perform the precondition check and to execute the command.
protected void	verifyPrecondition() Verify the precondition for the command after a lock has been obtain, just before executing the command.

Methods inherited from class org.apache.oozie.command.XCommand

call, eagerLoadState, eagerVerifyPrecondition, executeInterrupts, getCreatedTime, getInstrumentation, getKey, getLockTimeOut, getLog, getName, getPriority, getRequeueDelay, getType, inInterruptMode, isReQueueRequired, queue, queue, resetUsed, setInterruptMode

Methods inherited from class java.lang.Object

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

Constructor Detail

PurgeXCommand

public PurgeXCommand(int wfOlderThan,
                     int coordOlderThan,
                     int bundleOlderThan,
                     int limit)

Method Detail

loadState

protected void loadState()
                  throws CommandException

Description copied from class: XCommand

Load the necessary state to perform the precondition check and to execute the command.

Subclasses must implement this method and load the state needed to do the precondition check and execute the command.

Specified by:

loadState in class XCommand<Void>

Throws:

CommandException

execute

protected Void execute()
                throws CommandException

Description copied from class: XCommand

Command execution body.

This method will be invoked after the {link #loadState} and {link #verifyPrecondition} methods.

If the command requires locking, this method will be invoked ONLY if the lock has been acquired.

Specified by:

execute in class XCommand<Void>

Returns:

a return value from the execution of the command, only meaningful if the command is executed synchronously.

Throws:

CommandException - thrown if the command execution failed.

getEntityKey

public String getEntityKey()

Description copied from class: XCommand

Return the entity key for the command.

Specified by:

getEntityKey in interface XCallable<Void>

Specified by:

getEntityKey in class XCommand<Void>

Returns:

the entity key for the command.

isLockRequired

protected boolean isLockRequired()

Description copied from class: XCommand

Indicate if the the command requires locking.

Subclasses should override this method if they require locking.

Specified by:

isLockRequired in class XCommand<Void>

Returns:

true/false

verifyPrecondition

protected void verifyPrecondition()
                           throws CommandException,
                                  PreconditionException

Description copied from class: XCommand

Verify the precondition for the command after a lock has been obtain, just before executing the command.

Specified by:

verifyPrecondition in class XCommand<Void>

Throws:

CommandException - thrown if the precondition is not met.

PreconditionException