org.threadly.concurrent

Interface SchedulerService

All Superinterfaces:

java.util.concurrent.Executor, SubmitterExecutor, SubmitterScheduler

All Known Subinterfaces:

PrioritySchedulerService, StatisticPriorityScheduler

All Known Implementing Classes:

AbstractPriorityScheduler, DefaultPriorityWrapper, NoThreadScheduler, NoThreadSchedulerStatisticTracker, PriorityDelegatingScheduler, PriorityScheduler, PrioritySchedulerServiceQueueLimitRejector, PrioritySchedulerStatisticTracker, PrioritySchedulerTaskInterceptor, SchedulerServiceLimiter, SchedulerServiceQueueLimitRejector, SchedulerServiceTaskInterceptor, SingleThreadScheduler, SingleThreadSchedulerStatisticTracker, SingleThreadSchedulerSubPool, ThreadRenamingPriorityScheduler, ThreadRenamingSchedulerService

public interface SchedulerService
extends SubmitterScheduler

This interface adds some more advanced features to a scheduler that are more service oriented. Things like a concept of running/shutdown, as well as removing tasks are not always easy to implement.

Since:

4.3.0 (since 2.0.0 as SchedulerServiceInterface)

Method Summary

Modifier and Type	Method and Description
int	getActiveTaskCount() Call to check how many tasks are currently being executed in this scheduler.
int	getQueuedTaskCount() Returns how many tasks are either waiting to be executed, or are scheduled to be executed at a future point.
int	getWaitingForExecutionTaskCount() Returns how many tasks are either waiting to be executed.
boolean	isShutdown() Function to check if the thread pool is currently accepting and handling tasks.
boolean	remove(java.util.concurrent.Callable<?> task) Removes the callable task from the execution queue.
boolean	remove(java.lang.Runnable task) Removes the runnable task from the execution queue.

Methods inherited from interface org.threadly.concurrent.SubmitterScheduler

schedule, scheduleAtFixedRate, scheduleWithFixedDelay, submitScheduled, submitScheduled, submitScheduled

Methods inherited from interface org.threadly.concurrent.SubmitterExecutor

submit, submit, submit

Methods inherited from interface java.util.concurrent.Executor

execute

Method Detail

remove

boolean remove(java.lang.Runnable task)

Removes the runnable task from the execution queue. It is possible for the runnable to still run until this call has returned.

Note that this call has high guarantees on the ability to remove the task (as in a complete guarantee). But while this is being invoked, it will reduce the throughput of execution, so should NOT be used extremely frequently.

For non-recurring tasks using a future and calling Future.cancel(boolean) can be a better solution.

Parameters:

task - The original runnable provided to the executor

Returns:

true if the runnable was found and removed

remove

boolean remove(java.util.concurrent.Callable<?> task)

Removes the callable task from the execution queue. It is possible for the callable to still run until this call has returned.

Note that this call has high guarantees on the ability to remove the task (as in a complete guarantee). But while this is being invoked, it will reduce the throughput of execution, so should NOT be used extremely frequently.

For non-recurring tasks using a future and calling Future.cancel(boolean) can be a better solution.

Parameters:

task - The original callable provided to the executor

Returns:

true if the callable was found and removed

getActiveTaskCount

int getActiveTaskCount()

Call to check how many tasks are currently being executed in this scheduler.

Returns:

current number of running tasks

getQueuedTaskCount

int getQueuedTaskCount()

Returns how many tasks are either waiting to be executed, or are scheduled to be executed at a future point. This can indicate pool back pressure, but it can also just indicate generally scheduled tasks. It's computationally cheaper than getWaitingForExecutionTaskCount().

Returns:

quantity of tasks waiting execution or scheduled to be executed later

getWaitingForExecutionTaskCount

int getWaitingForExecutionTaskCount()

Returns how many tasks are either waiting to be executed. A value here can indicate the pool is being starved for threads.

Returns:

quantity of tasks waiting execution

isShutdown

boolean isShutdown()

Function to check if the thread pool is currently accepting and handling tasks.

Returns:

true if thread pool is running