/* ROT-1 server. Java version of: https://github.com/cirosantilli/cpp-cheat/tree/f31150c42331407fd434a7e912ca64642710fea2/posix/socket/inet */ import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.io.PrintStream; import java.net.ServerSocket; import java.net.Socket; public class ServerSocketCheat { public static void main(String[] args) throws IOException { final int port = 12345; ServerSocket listener = new ServerSocket(port); System.out.printf("listening on port %d%n", port); while (true) { System.out.println("waiting for client"); Socket socket = listener.accept(); System.out.printf("client connected from: %s%n", socket.getRemoteSocketAddress().toString()); BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream())); PrintStream out = new PrintStream(socket.getOutputStream()); for (String inputLine; (inputLine = in.readLine()) != null;) { System.out.println("received:"); System.out.println(inputLine); StringBuilder outputStringBuilder = new StringBuilder(""); char inputLineChars[] = inputLine.toCharArray(); for (char c : inputLineChars) outputStringBuilder.append(Character.toChars(c + 1)); out.println(outputStringBuilder); } socket.close(); } // Unreachable: user must Ctrl + C to exit. //listener.close(); } }