How to receive Broadcast message in java

Question

I am new to the area of computer networks so please bear with me. Below is the code I am using to broadcast datapacket over internet from the server but I do not know how to receive the broadcasted message at client side. Can anybody help me with that?

import java.net.*;
import java.io.*;

public class broadcast_message {
    private static DatagramSocket socket = null;

    public static void main(String[] args) throws IOException {
        broadcast("Hello", InetAddress.getByName("255.255.255.255"));
        System.out.println("Sent");
    }

    public static void broadcast(String broadcastMessage, InetAddress address) throws IOException {
        socket = new DatagramSocket();
        socket.setBroadcast(true);

        byte[] buffer = broadcastMessage.getBytes();

        DatagramPacket packet 
          = new DatagramPacket(buffer, buffer.length, address, 4000);
        socket.send(packet);
        socket.close();
    }
}

Answer 1

Your code sends a message to a port, but no one is there to receive it.

You need to create a socket listener to the same port (4000), before you send the message so that your socket listener receives the message.

See this post for example: sending and receiving UDP packets using Java?