org.apache.flink.streaming.runtime.tasks

接口 ProcessingTimeService

所有已知子接口:

TimerService

所有已知实现类:

SystemProcessingTimeService, TestProcessingTimeService

public interface ProcessingTimeService

Defines the current processing time and handles all related actions, such as register timers for tasks to be executed in the future.

The access to the time via getCurrentProcessingTime() is always available, regardless of whether the timer service has been shut down.

方法概要

限定符和类型	方法和说明
long	getCurrentProcessingTime() Returns the current processing time.
CompletableFuture<Void>	quiesce() This method puts the service into a state where it does not register new timers, but returns for each call to registerTimer(long, org.apache.flink.streaming.runtime.tasks.ProcessingTimeCallback) or scheduleAtFixedRate(org.apache.flink.streaming.runtime.tasks.ProcessingTimeCallback, long, long) a "mock" future and the "mock" future will be never completed.
ScheduledFuture<?>	registerTimer(long timestamp, ProcessingTimeCallback target) Registers a task to be executed when (processing) time is timestamp.
ScheduledFuture<?>	scheduleAtFixedRate(ProcessingTimeCallback callback, long initialDelay, long period) Registers a task to be executed repeatedly at a fixed rate.
ScheduledFuture<?>	scheduleWithFixedDelay(ProcessingTimeCallback callback, long initialDelay, long period) Registers a task to be executed repeatedly with a fixed delay.

方法详细资料

getCurrentProcessingTime

long getCurrentProcessingTime()

Returns the current processing time.

registerTimer

ScheduledFuture<?> registerTimer(long timestamp,
                                 ProcessingTimeCallback target)

Registers a task to be executed when (processing) time is timestamp.

参数:

timestamp - Time when the task is to be executed (in processing time)

target - The task to be executed

返回:

The future that represents the scheduled task. This always returns some future, even if the timer was shut down

scheduleAtFixedRate

ScheduledFuture<?> scheduleAtFixedRate(ProcessingTimeCallback callback,
                                       long initialDelay,
                                       long period)

Registers a task to be executed repeatedly at a fixed rate.

This call behaves similar to ScheduledExecutor.scheduleAtFixedRate(Runnable, long, long, TimeUnit).

参数:

callback - to be executed after the initial delay and then after each period

initialDelay - initial delay to start executing callback

period - after the initial delay after which the callback is executed

返回:

Scheduled future representing the task to be executed repeatedly

scheduleWithFixedDelay

ScheduledFuture<?> scheduleWithFixedDelay(ProcessingTimeCallback callback,
                                          long initialDelay,
                                          long period)

Registers a task to be executed repeatedly with a fixed delay.

This call behaves similar to ScheduledExecutor.scheduleWithFixedDelay(Runnable, long, long, TimeUnit).

参数:

callback - to be executed after the initial delay and then after each period

initialDelay - initial delay to start executing callback

period - after the initial delay after which the callback is executed

返回:

Scheduled future representing the task to be executed repeatedly

quiesce

CompletableFuture<Void> quiesce()

This method puts the service into a state where it does not register new timers, but returns for each call to registerTimer(long, org.apache.flink.streaming.runtime.tasks.ProcessingTimeCallback) or scheduleAtFixedRate(org.apache.flink.streaming.runtime.tasks.ProcessingTimeCallback, long, long) a "mock" future and the "mock" future will be never completed. Furthermore, the timers registered before are prevented from firing, but the timers in running are allowed to finish.

If no timer is running, the quiesce-completed future is immediately completed and returned. Otherwise, the future returned will be completed when all running timers have finished.