org.apache.oozie.command

Class SchemaCheckXCommand

java.lang.Object

org.apache.oozie.command.XCommand<Void>

org.apache.oozie.command.SchemaCheckXCommand

All Implemented Interfaces:

Callable<Void>, XCallable<Void>

public class SchemaCheckXCommand
extends XCommand<Void>

Field Summary

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

DEFAULT_LOCK_TIMEOUT, DEFAULT_REQUEUE_DELAY, dryrun, eventService, instrumentation, INSTRUMENTATION_GROUP

Constructor Summary

Constructors

Constructor and Description
SchemaCheckXCommand(String dbType, String url, String user, String pass, boolean ignoreExtras)

Method Summary

Modifier and Type	Method and Description
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, setLogInfo, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

SchemaCheckXCommand

public SchemaCheckXCommand(String dbType,
                           String url,
                           String user,
                           String pass,
                           boolean ignoreExtras)

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.

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

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

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.