Question

I have a program that sends requests to a server. There are many different types of request, and each has their own class. For example, I have a checkServerOnlineRequest which sends a short message to the server, or a getAmountOfGoldRequest which sends a very different message.

class CheckServerOnlineReq{
    static final byte requestID = 1;
    byte[] message;

    void setMessage(byte messageNumber){
        message = new byte[2];
        message[0] = messageNumber;
        message[1] = requestID;
    }
}

To send the requests, I have a Client class. It has static method called send which I would like to accept any type of request (i.e. a number of different classes)

My question is, how can I set up send()‘s parameters to allow any type of request to be given as an argument.

Answer 1

The canonical way is to declare an interface, and make the concrete request classes implement that interface:

public interface IRequest { ... }

public class CheckServerOnlineRequest implements IRequest { ... }
public class GetAmountOfGoldRequest implements IRequest { ... }

Then the send() method can accept IRequest as its argument.

public static void send(IRequest request) { ... }