Experience with gRPC and REST?

gRPC is a modern framework for remote procedure calls (RPC), based on HTTP/2 and using Protocol Buffers for data serialization. It provides high performance, streaming support, and a strictly typed contract between client and server.

REST is an architectural style for building web services, using HTTP methods (GET, POST, PUT, DELETE) and typically JSON or XML for data transfer. REST is simpler to implement and widely supported.

In Java, gRPC usually uses the official grpc-java library, where services are described in .proto files, code is generated, and server and client are implemented. For REST, Spring Boot with @RestController annotations is often used.

Example of a gRPC service in Java:

// Generated interface
public class HelloServiceGrpc {
    public static class HelloServiceImplBase {
        public void sayHello(HelloRequest req, StreamObserver<HelloResponse> responseObserver) {
            HelloResponse response = HelloResponse.newBuilder()
                .setMessage("Hello, " + req.getName())
                .build();
            responseObserver.onNext(response);
            responseObserver.onCompleted();
        }
    }
}

Example of a REST controller in Spring Boot:

@RestController
public class HelloController {
    @GetMapping("/hello")
    public String sayHello(@RequestParam String name) {
        return "Hello, " + name;
    }
}