HelloWorldClient.java

package io.grpc.examples.helloworld;

import io.grpc.ManagedChannel;
import io.grpc.ManagedChannelBuilder;
import io.grpc.StatusRuntimeException;
import io.grpc.stub.StreamObserver;

import java.util.concurrent.TimeUnit;
import java.util.logging.Level;
import java.util.logging.Logger;


public class HelloWorldClient {

  private static final Logger logger = Logger.getLogger(HelloWorldClient.class.getName());

  private final GreeterGrpc.GreeterStub stub;

  /** Construct client for accessing HelloWorld server using the existing channel. */
  public HelloWorldClient(ManagedChannel channel) {
    stub = GreeterGrpc.newStub(channel);
  }

  /** Say hello to server. */
  public void greet(String name, StreamObserver<HelloReply> responseObserver) {
    HelloRequest request = HelloRequest.newBuilder().setName(name).build();
    try {
      stub.withDeadlineAfter(10, TimeUnit.MILLISECONDS).sayHello(request, responseObserver);

    } catch (StatusRuntimeException e) {
      logger.log(Level.WARNING, "RPC failed: {0}", e.getStatus());
      return;
    }
  }

  public static void main(String[] args) throws Exception {
    ManagedChannel channel =
        ManagedChannelBuilder.forTarget("localhost:50051").usePlaintext().build();
    HelloWorldClient client = new HelloWorldClient(channel);
    while (true) {
      client.greet("a".repeat(100000), responseObserver);
      Thread.sleep(1);
    }
  }

  static StreamObserver<HelloReply> responseObserver =
      new StreamObserver<HelloReply>() {
        @Override
        public void onNext(HelloReply reply) {
        }

        @Override
        public void onError(Throwable t) {
          logger.info(t.getMessage());
        }

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