Package io.grpc.stub

Class ServerCallStreamObserver<V>

  • All Implemented Interfaces:
    StreamObserver<V>
    @ExperimentalApi("https://github.com/grpc/grpc-java/issues/1788")
public abstract class ServerCallStreamObserver<V>
extends CallStreamObserver<V>
    A refinement of CallStreamObserver to allows for interaction with call cancellation events on the server side.

    Like StreamObserver, implementations are not required to be thread-safe; if multiple threads will be writing to an instance concurrently, the application must synchronize its calls.

    DO NOT MOCK: The API is too complex to reliably mock. Use InProcessChannelBuilder to create "real" RPCs suitable for testing and interact with the server using a normal client stub.

    • Constructor Detail

      • ServerCallStreamObserver

        public ServerCallStreamObserver()

    • Method Detail

      • isCancelled

        public abstract boolean isCancelled()
        If true indicates that the call has been cancelled by the remote peer.

        This method may safely be called concurrently from multiple threads.

      • setOnCancelHandler

        public abstract void setOnCancelHandler​(java.lang.Runnable onCancelHandler)
        Set a Runnable that will be called if the calls isCancelled() state changes from false to true. It is guaranteed that execution of the Runnable are serialized with calls to the 'inbound' StreamObserver.

        Note that the handler may be called some time after isCancelled() has transitioned to true as other callbacks may still be executing in the 'inbound' observer.

        Setting the onCancelHandler will suppress the on-cancel exception thrown by StreamObserver.onNext(V).

        Parameters:
        onCancelHandler - to call when client has cancelled the call.

      • setCompression

        public abstract void setCompression​(java.lang.String compression)
        Sets the compression algorithm to use for the call. May only be called before sending any messages. Default gRPC servers support the "gzip" compressor.

        It is safe to call this even if the client does not support the compression format chosen. The implementation will handle negotiation with the client and may fall back to no compression.

        Parameters:
        compression - the compression algorithm to use.
        Throws:
        java.lang.IllegalArgumentException - if the compressor name can not be found.