Package com.google.api.gax.rpc

Class Watchdog

java.lang.Object

com.google.api.gax.rpc.Watchdog

All Implemented Interfaces:

BackgroundResource, AutoCloseable, Runnable

public final class Watchdog
extends Object
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.

Method Summary

Modifier and Type	Method	Description
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.
void	close()
static Watchdog	create(ApiClock clock, org.threeten.bp.Duration scheduleInterval, ScheduledExecutorService executor)	returns a Watchdog which is scheduled at the provided interval.
boolean	isShutdown()	Returns true if this background resource has been shut down.
boolean	isTerminated()	Returns true if all work has completed following shut down.
void	run()
void	shutdown()	Initiates an orderly shutdown in which previously submitted work is finished, but no new work will be accepted.
void	shutdownNow()	Attempts to stop all actively executing work and halts the processing of waiting work.
<ResponseT> ResponseObserver<ResponseT>	watch(ResponseObserver<ResponseT> innerObserver, org.threeten.bp.Duration waitTimeout, org.threeten.bp.Duration idleTimeout)	Wraps the target observer with timing constraints.

Methods inherited from class java.lang.Object

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

Method Detail

create

public static Watchdog create(ApiClock clock,
                              org.threeten.bp.Duration scheduleInterval,
                              ScheduledExecutorService executor)

returns a Watchdog which is scheduled at the provided interval.

watch

public <ResponseT> ResponseObserver<ResponseT> watch(ResponseObserver<ResponseT> innerObserver,
                                                     @Nonnull
                                                     org.threeten.bp.Duration waitTimeout,
                                                     @Nonnull
                                                     org.threeten.bp.Duration idleTimeout)

Wraps the target observer with timing constraints.

run

public void run()

Specified by:

run in interface Runnable

shutdown

public void shutdown()

Description copied from interface: BackgroundResource

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.

Specified by:

shutdown in interface BackgroundResource

isShutdown

public boolean isShutdown()

Description copied from interface: BackgroundResource

Returns true if this background resource has been shut down.

Specified by:

isShutdown in interface BackgroundResource

isTerminated

public boolean isTerminated()

Description copied from interface: BackgroundResource

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

Specified by:

isTerminated in interface BackgroundResource

shutdownNow

public void shutdownNow()

Description copied from interface: BackgroundResource

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.

Specified by:

shutdownNow in interface BackgroundResource

awaitTermination

public boolean awaitTermination(long duration,
                                TimeUnit unit)
                         throws InterruptedException

Description copied from interface: BackgroundResource

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

Specified by:

awaitTermination in interface BackgroundResource

Throws:

InterruptedException

close

public void close()

Specified by:

close in interface AutoCloseable