Class Watchdog (2.19.0)

public final class Watchdog implements Runnable, BackgroundResource

Prevents the streams from hanging indefinitely. This middleware garbage collects idle streams in case the user forgot to close a ServerStream or if a connection is reset and GRPC does not get notified.

For every checkInterval, this class checks two thresholds:

  • waitingTimeout: the amount of time to wait for a response (after the caller signaled demand) before forcefully closing the stream. Duration.ZERO disables the timeout.
  • idleTimeout: the amount of time to wait before assuming that the caller forgot to close the stream and forcefully closing the stream. This is measured from the last time the caller had no outstanding demand. Duration.ZERO disables the timeout.

Inheritance

java.lang.Object > Watchdog

Static Methods

create(ApiClock clock, Duration scheduleInterval, ScheduledExecutorService executor)

public static Watchdog create(ApiClock clock, Duration scheduleInterval, ScheduledExecutorService executor)

returns a Watchdog which is scheduled at the provided interval.

Parameters
NameDescription
clockcom.google.api.core.ApiClock
scheduleIntervalorg.threeten.bp.Duration
executorScheduledExecutorService
Returns
TypeDescription
Watchdog

Methods

<ResponseT>watch(ResponseObserver<ResponseT> innerObserver, Duration waitTimeout, Duration idleTimeout)

public ResponseObserver<ResponseT> <ResponseT>watch(ResponseObserver<ResponseT> innerObserver, Duration waitTimeout, Duration idleTimeout)

Wraps the target observer with timing constraints.

Parameters
NameDescription
innerObserverResponseObserver<ResponseT>
waitTimeoutorg.threeten.bp.Duration
idleTimeoutorg.threeten.bp.Duration
Returns
TypeDescription
ResponseObserver<ResponseT>

awaitTermination(long duration, TimeUnit unit)

public boolean awaitTermination(long duration, TimeUnit unit)

Blocks until all work has completed execution after a shutdown request, or the timeout occurs, or the current thread is interrupted, whichever happens first.

Parameters
NameDescription
durationlong
unitTimeUnit
Returns
TypeDescription
boolean
Exceptions
TypeDescription
InterruptedException

close()

public void close()

isShutdown()

public boolean isShutdown()

Returns true if this background resource has been shut down.

Returns
TypeDescription
boolean

isTerminated()

public boolean isTerminated()

Returns true if all work has completed following shut down. Note that isTerminated is never true unless either shutdown or shutdownNow was called first.

Returns
TypeDescription
boolean

run()

public void run()

shutdown()

public void shutdown()

Initiates an orderly shutdown in which previously submitted work is finished, but no new work will be accepted. Invocation has no additional effect if already shut down.

This method does not wait for previously submitted work to complete execution. Use awaitTermination to do that.

shutdownNow()

public void shutdownNow()

Attempts to stop all actively executing work and halts the processing of waiting work.

This method does not wait for actively executing work to terminate. Use awaitTermination to do that.

There are no guarantees beyond best-effort attempts to stop processing actively executing work. For example, typical implementations will cancel via Thread.interrupt(), so any task that fails to respond to interrupts may never terminate.