java listen on port code example

Example 1: how to listen to a port in java

int portNumber = Integer.parseInt(args[0]);

try ( 
    ServerSocket serverSocket = new ServerSocket(portNumber);
    Socket clientSocket = serverSocket.accept();
    PrintWriter out =
        new PrintWriter(clientSocket.getOutputStream(), true);
    BufferedReader in = new BufferedReader(
        new InputStreamReader(clientSocket.getInputStream()));
) {

Example 2: listen to port

app.express.listen(PORT, () => {
 console.log(`App listening on port ${PORT}`);
});