Server.java

import javax.net.ssl.*;
import java.io.*;
import java.security.KeyStore;

public class Server {
    public static void main(String[] args) throws Exception {
        int port = 4000;

        // Load the server keystore
        KeyStore keyStore = KeyStore.getInstance("JKS");
        keyStore.load(new FileInputStream("serverkey.jks"), "stpass123".toCharArray()); // Update with your keystore password

        // Initialize KeyManagerFactory with the server's keystore
        KeyManagerFactory keyManagerFactory = KeyManagerFactory.getInstance(KeyManagerFactory.getDefaultAlgorithm());
        keyManagerFactory.init(keyStore, "stpass123".toCharArray()); // Update with your key password

        // Initialize SSLContext
        SSLContext sslContext = SSLContext.getInstance("TLS");
        sslContext.init(keyManagerFactory.getKeyManagers(), null, null);

        // Create SSL ServerSocket
        SSLServerSocketFactory serverSocketFactory = sslContext.getServerSocketFactory();
        SSLServerSocket serverSocket = (SSLServerSocket) serverSocketFactory.createServerSocket(port);
        System.out.println("Secure server started on port " + port);

        while (true) {
            SSLSocket clientSocket = (SSLSocket) serverSocket.accept();
            System.out.println("Client connected: " + clientSocket.getInetAddress());

            // Communication with the client
            BufferedReader input = new BufferedReader(new InputStreamReader(clientSocket.getInputStream()));
            PrintWriter output = new PrintWriter(clientSocket.getOutputStream(), true);

            String message;
            while ((message = input.readLine()) != null) {
                System.out.println("Received from client: " + message);
                output.println("Hello, client! Secure communication established.");
            }

            clientSocket.close();
        }
    }
}