org.apache.oozie.command.coord
Class CoordActionInputCheckXCommand

java.lang.Object
  org.apache.oozie.command.XCommand<T>
      org.apache.oozie.command.coord.CoordinatorXCommand<Void>
          org.apache.oozie.command.coord.CoordActionInputCheckXCommand

All Implemented Interfaces:

Callable<Void>, XCallable<Void>

public class CoordActionInputCheckXCommand
extends CoordinatorXCommand<Void>

The command to check if an action's data input paths exist in the file system.

Field Summary

static String

CONF_COORD_INPUT_CHECK_REQUEUE_INTERVAL Property name of command re-queue interval for coordinator action input check in milliseconds.

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

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

Constructor Summary

CoordActionInputCheckXCommand(String actionId, String jobId)

Method Summary

protected boolean	checkInput(StringBuilder actionXml, StringBuilder existList, StringBuilder nonExistList, org.apache.hadoop.conf.Configuration conf) To check the list of input paths if all of them exist
protected void	eagerLoadState() Load the necessary state to perform an eager precondition check.
protected Void	execute() Command execution body.
long	getCoordInputCheckRequeueInterval() This function reads the value of re-queue interval for coordinator input check command from the Oozie configuration provided by Configuration Service.
String	getEntityKey() Return the entity key for the command.
String	getKey() Get command key
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, eagerVerifyPrecondition, executeInterrupts, getCreatedTime, getInstrumentation, 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

Field Detail

CONF_COORD_INPUT_CHECK_REQUEUE_INTERVAL

public static final String CONF_COORD_INPUT_CHECK_REQUEUE_INTERVAL

Property name of command re-queue interval for coordinator action input check in milliseconds.

See Also:

Constant Field Values

Constructor Detail

CoordActionInputCheckXCommand

public CoordActionInputCheckXCommand(String actionId,
                                     String jobId)

Method Detail

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.

getCoordInputCheckRequeueInterval

public long getCoordInputCheckRequeueInterval()

This function reads the value of re-queue interval for coordinator input check command from the Oozie configuration provided by Configuration Service. If nothing defined in the configuration, it uses the code specified default value.

Returns:

re-queue interval in ms

checkInput

protected boolean checkInput(StringBuilder actionXml,
                             StringBuilder existList,
                             StringBuilder nonExistList,
                             org.apache.hadoop.conf.Configuration conf)
                      throws Exception

To check the list of input paths if all of them exist

Parameters:

actionXml - action xml

existList - the list of existed paths

nonExistList - the list of non existed paths

conf - action configuration

Returns:

true if all input paths are existed

Throws:

Exception - thrown of unable to check input path

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

eagerLoadState

protected void eagerLoadState()
                       throws CommandException

Description copied from class: XCommand

Load the necessary state to perform an eager precondition check.

This implementation does a NOP.

Subclasses should override this method and load the state needed to do an eager precondition check.

A trivial implementation is calling {link #loadState}.

Overrides:

eagerLoadState in class XCommand<Void>

Throws:

CommandException

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

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

getKey

public String getKey()

Description copied from class: XCommand

Get command key

Specified by:

getKey in interface XCallable<Void>

Overrides:

getKey in class XCommand<Void>

Returns:

command key