GreeterClient.java

package com.example;

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

public class GreeterClient {
    public static void main(String[] args) {
        String host = "localhost";
        int port = 50051;
        ManagedChannel channel = ManagedChannelBuilder.forAddress(host, port).usePlaintext().build();
        GreeterGrpc.GreeterBlockingStub blockingStub = GreeterGrpc.newBlockingStub(channel);
        HelloRequest request = HelloRequest.newBuilder().setName("World").build();
        try {
            HelloReply response = blockingStub.sayHello(request);
            String message = response.getMessage();
            System.out.println(message);
        } catch (StatusRuntimeException e) {
            System.err.println("RPC failed: " + e.getStatus());
        }
    }
}