Package com.google.api.gax.rpc

Class Watchdog

  • All Implemented Interfaces:
    BackgroundResource, java.lang.AutoCloseable, java.lang.Runnable
    public final class Watchdog
extends java.lang.Object
implements java.lang.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

      All Methods Static Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      boolean awaitTermination​(long duration, java.util.concurrent.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​(com.google.api.core.ApiClock clock, org.threeten.bp.Duration scheduleInterval, java.util.concurrent.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​(com.google.api.core.ApiClock clock,
                              org.threeten.bp.Duration scheduleInterval,
                              java.util.concurrent.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 java.lang.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

      • 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,
                                java.util.concurrent.TimeUnit unit)
                         throws java.lang.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:
        java.lang.InterruptedException

      • close

        public void close()
        Specified by:
        close in interface java.lang.AutoCloseable