[JAVA] Swift Network.framework Study 2019 1207 "Server UDP"

Study

Network.framework Study: Server side

environment

Client：Java、NetBeans Server：Swift、Xcode

Client Source Java

package example.java.network;

import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;

public class ExampleClientUDP {
    public static void main(String[] args) {
        String sendData = "Send Data Example";
        try {
            DatagramSocket datagramSocket = new DatagramSocket();
            DatagramPacket datagramPacke = new DatagramPacket(sendData.getBytes(), sendData.getBytes().length, InetAddress.getByName("localhost"), 7777);
            datagramSocket.send(datagramPacke);
        }
        catch(Exception e) {
            System.out.println(e);
        }
    }
}

Server Source Swift

Use NWLister Just change from the tcp version to ".udp".

main.swift

import Foundation
import Network

var networkServer = NetworkServer()

networkServer.startListener()

while networkServer.running {
    sleep(1)
}

NetworkServer.swift

import Foundation
import Network

class NetworkServer {
    public var running = true

    func startListener() {
        let myQueue = DispatchQueue(label: "ExampleNetwork")

        do {
            let nWListener = try NWListener(using: .udp, on: 7777)
            nWListener.newConnectionHandler = { (newConnection) in
                print("New Connection!!")
                newConnection.start(queue: myQueue)
                self.receive(nWConnection: newConnection)
            }
            nWListener.start(queue: myQueue)
            print("start")
        }
        catch {
            print(error)
        }
    }
    
    func receive(nWConnection:NWConnection) {
        nWConnection.receive(minimumIncompleteLength: 1, maximumLength: 5, completion: { (data, context, flag, error) in
            print("receiveMessage")
            if let data = data {
                let receiveData = [UInt8](data)
                print(receiveData)
                print(flag)
                if(flag == false) {
                    self.receive(nWConnection: nWConnection)
                }
            }
            else {
                print("receiveMessage data nil")
            }
        })
    }
    
}