org.glassfish.hk2.runlevel

Interface RunLevelFuture

All Superinterfaces:

Future<Object>

All Known Subinterfaces:

ChangeableRunLevelFuture

All Known Implementing Classes:

CurrentTaskFuture, CurrentTaskFutureWrapper

public interface RunLevelFuture
extends Future<Object>

This is the Future object that will be returned by the RunLevelController and it contains extra information about the job being done

Author:

jwells

Method Summary

Methods

Modifier and Type	Method and Description
boolean	cancel(boolean mayInterruptIfRunning) The cancel method attempts to cancel the current running job (if the job is not already completed or already cancelled).
int	getProposedLevel() This gets the level that this future job is attempting to get to
boolean	isDown() Returns true if this job represents the system going from a higher level to a lower level.
boolean	isUp() Returns true if this job represents the system going from a lower level to a higher level.

Methods inherited from interface java.util.concurrent.Future

get, get, isCancelled, isDone

Method Detail

getProposedLevel

int getProposedLevel()

This gets the level that this future job is attempting to get to

Returns:

The level that this future job is attempting to go to

isUp

boolean isUp()

Returns true if this job represents the system going from a lower level to a higher level. This method and isDown can both be false (for the case that proceedTo asked to go to the level it is already at) but they cannot both be true

Returns:

true if this job was proceeding from a lower level to a higher level

isDown

boolean isDown()

Returns true if this job represents the system going from a higher level to a lower level. This method and isUp can both be false (for the case that proceedTo asked to go to the level it is already at) but they cannot both be true

Returns:

true if this job was proceeding from a higher level to a lower level

cancel

boolean cancel(boolean mayInterruptIfRunning)

The cancel method attempts to cancel the current running job (if the job is not already completed or already cancelled). The meaning of cancel is different depending on whether or not the system was going up to a level or coming down to a level.

If the system was going up to a level then calling cancel will cause the system to stop going up, and instead proceed back down to the last completed level. For example, suppose there were three services at level ten and the system was going up to level ten. As the system was proceeding up to level ten the first of the three services had already been started and the second service was in progress and the third service had not been started. The system will wait for the second service to complete coming up and then will shut it down along with the first service. Since the last completed level was nine, the system will remain at level nine and this job will be complete.

If the system was going down to a level then calling cancel will cause the system to continue going down, but it will stop going down at the next level. For example, suppose there were three services at level ten and the current proposed level is five. Suppose one of those three services had already been shutdown and one was in the process of being shutdown and the other had not yet been shutdown when the cancel arrives. The system will continue to shutdown the one in progress and then will shutdown the remaining service at level ten to reach level nine. However, the job will no longer attempt to go down to level five, but will instead be finished at level nine.

There is a cancel timeout value that is set. This is the amount of time the system will wait for services to complete after cancel has been called. Any services still running after this timeout will be orphaned (they will not be shutdown if they do eventually complete). Further, if an attempt is made to start the same service that is still running on another thread that request will fail.

Specified by:

cancel in interface Future<Object>

Parameters:

mayInterruptIfRunning - is currently ignored