diff --git a/assignments/src/MV3500Cohort2021JulySeptember/homework1/FisherTCPExample1Telnet.java b/assignments/src/MV3500Cohort2021JulySeptember/homework1/FisherTCPExample1Telnet.java new file mode 100644 index 0000000000000000000000000000000000000000..483b40bf6e0256e6fd6486ebb3d5917e21040dd0 --- /dev/null +++ b/assignments/src/MV3500Cohort2021JulySeptember/homework1/FisherTCPExample1Telnet.java @@ -0,0 +1,64 @@ +package MV3500Cohort2021JulySeptember.homework1; + + +import java.io.IOException; +import java.io.OutputStream; +import java.io.PrintStream; +import java.net.ServerSocket; +import java.net.Socket; + +/** + * + * @author adfis + */ + + +public class FisherTCPExample1Telnet { + public static void main(String[] args) + { + try + { + System.out.println("TcpExample1Telnet has started and is waiting for a connection."); + System.out.println(" help: https://savage.nps.edu/Savage/developers.html#telnet"); + System.out.println(" enter (telnet localhost 2317) or (nc localhost 2317)..." ); + + // The ServerSocket waits for a connection from a client. + // It returns a Socket object when the connection occurs. + ServerSocket serverSocket = new ServerSocket(2317); + + // Use Java io classes to write text (as opposed to + // unknown bytes of some sort) to the client + + // The Socket object represents the connection between + // the server and client, including a full duplex connection + try (Socket clientConnection = serverSocket.accept()) { + // Use Java io classes to write text (as opposed to + // unknown bytes of some sort) to the client + OutputStream os = clientConnection.getOutputStream(); + PrintStream ps = new PrintStream(os); + + ps.println("Client response was written by Alex' server TcpExample1."); // to remote clientnc + ps.println("We are crushing this assignment, good work."); + System.out.println("Server response was written by Alex' server TcpExample1."); // to server console + System.out.println("SUCCESS!"); + + // "flush()" in important in that it forces a write + // across what is in fact a slow connection + ps.flush(); + } + System.out.println("TcpExample1 completed successfully."); + } + catch(IOException e) + { + System.err.println("Problem with TcpExample1Telnet networking:"); // describe what is happening + System.err.println("Error: " + e); + // Provide more helpful information to user if exception occurs due to running twice at one time + + // brute force exception checking, can be brittle if exception message changes + // if (e.getMessage().equals("Address already in use: NET_Bind")) + if (e instanceof java.net.BindException) + System.err.println("*** Be sure to stop any other running instances of programs using this port!"); + } + } +} +