io.grpc.stub.ServerCallStreamObserver Maven / Gradle / Ivy
/*
* Copyright 2016 The gRPC Authors
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package io.grpc.stub;
import io.grpc.ExperimentalApi;
/**
* A refinement of {@link CallStreamObserver} to allows for interaction with call
* cancellation events on the server side.
*
* Like {@code 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.
*/
@ExperimentalApi("https://github.com/grpc/grpc-java/issues/1788")
public abstract class ServerCallStreamObserver extends CallStreamObserver {
/**
* If {@code true} indicates that the call has been cancelled by the remote peer.
*
* This method may safely be called concurrently from multiple threads.
*/
public abstract boolean isCancelled();
/**
* Set a {@link Runnable} that will be called if the calls {@link #isCancelled()} state
* changes from {@code false} to {@code true}. It is guaranteed that execution of the
* {@link Runnable} are serialized with calls to the 'inbound' {@link StreamObserver}.
*
*
Note that the handler may be called some time after {@link #isCancelled()} has transitioned
* to {@code true} as other callbacks may still be executing in the 'inbound' observer.
*
*
Setting the onCancelHandler will suppress the on-cancel exception thrown by
* {@link #onNext}.
*
* @param onCancelHandler to call when client has cancelled the call.
*/
public abstract void setOnCancelHandler(Runnable onCancelHandler);
/**
* 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.
*
* @param compression the compression algorithm to use.
* @throws IllegalArgumentException if the compressor name can not be found.
*/
public abstract void setCompression(String compression);
}