sirius.kernel.async

Class DelayLine

java.lang.Object

sirius.kernel.async.BackgroundLoop

sirius.kernel.async.DelayLine

All Implemented Interfaces:

MetricProvider

public class DelayLine
extends BackgroundLoop
implements MetricProvider

Permits to delay the execution of a task by a certain amount of seconds.

Provides a background queue, which is checked about every 500ms. All tasks, which delay is expired will be invoked in the given executor.

Note that this should not be used with large delays, but rather for short durations (e.g. less than 60 seconds, although this depends heavily on the use case, as there is no inherent limit other than tasks won't survive a system restart).

Constructor Summary

Constructors

Constructor and Description
DelayLine()

Method Summary

Modifier and Type	Method and Description
void	callDelayed(String executor, long delayInSeconds, Runnable task) Queues the given task to be called after roughly the number of seconds given here.
protected void	doWork() Executes the actual work.
void	forkDelayed(String executor, long delayInSeconds, Runnable task) Queues the given task to be called after roughly the number of seconds given here.
void	gather(MetricsCollector collector) Invoked roughly every minute to collect all available metrics.
String	getName() Returns the name of the loop.
protected double	maxCallFrequency() Determines the maximal call frequency of BackgroundLoop.doWork() in Hertz (ticks per second).

Methods inherited from class sirius.kernel.async.BackgroundLoop

determineExecutor, getExecutionInfo, loop, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

DelayLine

public DelayLine()

Method Detail

callDelayed

public void callDelayed(@Nonnull
                        String executor,
                        long delayInSeconds,
                        @Nonnull
                        Runnable task)

Queues the given task to be called after roughly the number of seconds given here.

Parameters:

executor - the executor to execute the task in. Use Tasks.DEFAULT is no other appropriate pool is available.

delayInSeconds - the number to wait in seconds. Note that the delay can be a bit longer, depending on the system load.

task - the task to execute. Note that the CallContext isn't transferred to the task being invoked. Use forkDelayed(String, long, Runnable) if you need the context.

forkDelayed

public void forkDelayed(@Nonnull
                        String executor,
                        long delayInSeconds,
                        @Nonnull
                        Runnable task)

Queues the given task to be called after roughly the number of seconds given here.

In contrast to callDelayed(String, long, Runnable), this will preserve the CallContext when invoking the task.

Parameters:

executor - the executor to execute the task in. Use Tasks.DEFAULT is no other appropriate pool is available.

delayInSeconds - the number to wait in seconds. Note that the delay can be a bit longer, depending on the system load.

task - the task to execute

getName

@Nonnull
public String getName()

Description copied from class: BackgroundLoop

Returns the name of the loop.

Specified by:

getName in class BackgroundLoop

Returns:

the name of the loop for reporting and logging

maxCallFrequency

protected double maxCallFrequency()

Description copied from class: BackgroundLoop

Determines the maximal call frequency of BackgroundLoop.doWork() in Hertz (ticks per second).

Overrides:

maxCallFrequency in class BackgroundLoop

Returns:

the maximal call frequency in Hertz.

doWork

protected void doWork()
               throws Exception

Description copied from class: BackgroundLoop

Executes the actual work.

Specified by:

doWork in class BackgroundLoop

Throws:

Exception - in case of any error. The outer loop has a catch all rule to log exceptions.

gather

public void gather(MetricsCollector collector)

Description copied from interface: MetricProvider

Invoked roughly every minute to collect all available metrics.

Specified by:

gather in interface MetricProvider

Parameters:

collector - the interface used to provide metrics