HelloServiceImpl.java

package me.dinowernli.grpc.polyglot.server;

import io.grpc.Status;
import io.grpc.stub.StreamObserver;
import polyglot.HelloProto.HelloRequest;
import polyglot.HelloProto.HelloResponse;
import polyglot.HelloServiceGrpc.HelloServiceImplBase;

public class HelloServiceImpl extends HelloServiceImplBase {
  private static final long STREAM_SLEEP_MILLIS = 250;
  private static final int STREAM_MESSAGES_NUMBER = 8;

  @Override
  public void sayHello(HelloRequest request, StreamObserver<HelloResponse> responseStream) {
    responseStream.onNext(HelloResponse.newBuilder()
        .setMessage("Hello, " + request.getRecipient())
        .build());
    responseStream.onCompleted();
  }

  @Override
  public void sayHelloStream(HelloRequest request, StreamObserver<HelloResponse> responseStream) {
    for (int i = 0; i < STREAM_MESSAGES_NUMBER; ++i) {
      responseStream.onNext(HelloResponse.newBuilder()
          .setMessage("Hello, " + request.getRecipient() + ", part " + i)
          .build());
      try {
        Thread.sleep(STREAM_SLEEP_MILLIS);
      } catch (InterruptedException e) {
        responseStream.onError(Status.ABORTED.asException());
      }
    }
    responseStream.onCompleted();
  }

  @Override
  public StreamObserver<HelloRequest> sayHelloBidi(
      final StreamObserver<HelloResponse> responseStream) {
    return new StreamObserver<HelloRequest>() {
      @Override
      public void onNext(HelloRequest request) {
        responseStream.onNext(HelloResponse.newBuilder()
          .setMessage("Hello, " + request.getRecipient())
          .build());
      }

      @Override
      public void onError(Throwable t) {
        responseStream.onError(Status.ABORTED.asException());
      }

      @Override
      public void onCompleted() {
        responseStream.onCompleted();
      }
    };
  }
}