What Are The Different Types Of Java Networking ?

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

public class TCPServer {
    public static void main(String[] args) {
        try {
            // Create a server socket listening on port 12345
            ServerSocket serverSocket = new ServerSocket(12345);
            System.out.println("Server started, waiting for client connection...");
            
            // Accept client connection
            Socket clientSocket = serverSocket.accept();
            System.out.println("Client connected!");
            
            // Create input and output streams
            BufferedReader input = new BufferedReader(new InputStreamReader(clientSocket.getInputStream()));
            PrintWriter output = new PrintWriter(clientSocket.getOutputStream(), true);
            
            // Read and respond to client messages
            String message = input.readLine();
            System.out.println("Client says: " + message);
            output.println("Server received: " + message);
            
            // Close resources
            clientSocket.close();
            serverSocket.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

Server started, waiting for client connection...
Client connected!
Client says: Hello Server!

import java.net.*;

public class UDPServer {
    public static void main(String[] args) {
        try {
            DatagramSocket socket = new DatagramSocket(12345);
            byte[] receiveData = new byte[1024];
            
            System.out.println("Server listening on port 12345...");
            
            // Receive data from client
            DatagramPacket receivePacket = new DatagramPacket(receiveData, receiveData.length);
            socket.receive(receivePacket);
            
            String message = new String(receivePacket.getData(), 0, receivePacket.getLength());
            System.out.println("Received from client: " + message);
            
            // Send response to client
            String response = "Server received: " + message;
            DatagramPacket sendPacket = new DatagramPacket(response.getBytes(), response.length(), receivePacket.getAddress(), receivePacket.getPort());
            socket.send(sendPacket);
            
            socket.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

Server listening on port 12345...
Received from client: Hello Server!

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

public class URLExample {
    public static void main(String[] args) {
        try {
            // Create URL object for the website
            URL url = new URL("http://www.kaashiv.com");
            
            // Open connection
            HttpURLConnection connection = (HttpURLConnection) url.openConnection();
            connection.setRequestMethod("GET");
            
            // Read response
            BufferedReader in = new BufferedReader(new InputStreamReader(connection.getInputStream()));
            String inputLine;
            StringBuffer response = new StringBuffer();
            while ((inputLine = in.readLine()) != null) {
                response.append(inputLine);
            }
            in.close();
            
            // Print the response content
            System.out.println(response.toString());
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

The output will be the HTML content of the page at http://www.kaashiv.com.

import java.net.*;

public class MulticastExample {
    public static void main(String[] args) {
        try {
            MulticastSocket socket = new MulticastSocket(12345);
            InetAddress group = InetAddress.getByName("230.0.0.1"); // Multicast address
            socket.joinGroup(group);
            
            // Send message to multicast group
            String message = "Hello, Multicast Group!";
            DatagramPacket packet = new DatagramPacket(message.getBytes(), message.length(), group, 12345);
            socket.send(packet);
            
            // Receive message from multicast group
            byte[] buffer = new byte[256];
            DatagramPacket receivePacket = new DatagramPacket(buffer, buffer.length);
            socket.receive(receivePacket);
            String response = new String(receivePacket.getData(), 0, receivePacket.getLength());
            System.out.println("Received: " + response);
            
            socket.leaveGroup(group);
            socket.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

import java.rmi.Naming;
import java.rmi.RemoteException;
import java.rmi.registry.LocateRegistry;
import java.rmi.registry.Registry;

// Create the Server Program
public class RMIServer {
    public static void main(String[] args) {
        try {
            // Create an instance of the remote object
            CalculatorImpl calc = new CalculatorImpl();
            
            // Create RMI registry if it does not exist
            LocateRegistry.createRegistry(1099);
            
            // Bind the remote object to a name in the RMI registry
            Naming.rebind("CalculatorService", calc);
            
            System.out.println("Server is ready.");
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

Server is ready.