SigPlace/sigServer.java

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.ServerSocket;
import java.net.Socket;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.regex.Pattern;

public class sigServer {
    ServerSocket socket;
    sigServer() {
        try {
            socket = new ServerSocket(8080);
            System.out.println("Listening on port 8080.");
            while (true) {
                try (Socket client = socket.accept()) {
                    System.out.println("New client connection detected: "+client.toString());
                    BufferedReader in = new BufferedReader(new InputStreamReader(client.getInputStream()));
                    String line;
                    line=in.readLine(); //Read the first line, this should be our request.
                    String[] splitter = line.split(Pattern.quote(" "));
                    if (splitter.length==3) {
                        //This is valid.
                        if (splitter[0].equals("GET")) { //This is a GET request.
                            if (splitter[2].equals("HTTP/1.1")||splitter[2].equals("HTTP/2.0")) {
                                String requestloc = splitter[1];
                                if (requestloc.equals("/")) {
                                    //Send default directory.
                                    CreateRequest(client,"200","OK","testfile.html");
                                } else {
                                    CreateRequest(client,"200","OK",Paths.get("/", requestloc.replace("/","")).toString());
                                }
                            }
                        } else {
                            CreateRequest(client,"501","Not Implemented","testfile.html");
                        }
                    }
                    while (!(line=in.readLine()).isBlank()) {
                        //System.out.println(line);
                    }
                }
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    private void CreateRawRequest(OutputStream stream, String statusCode, String statusMsg, String contentType, byte[] content) {
        try {
            stream.write(("HTTP/1.1 "+statusCode+" "+statusMsg+"\r\n").getBytes());
            stream.write(("ContentType: "+contentType+"\r\n").getBytes());
            stream.write("\r\n".getBytes());
            stream.write(content);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    private void CreateRequest(Socket client, String statusCode, String statusMsg, String string) {
        Path file = Paths.get(sigPlace.OUTDIR,string);
        try {
            OutputStream clientOutput = client.getOutputStream();
            if (statusCode.equals("200")) {
                if (Files.exists(file)) {
                    CreateRawRequest(clientOutput,statusCode,statusMsg,Files.probeContentType(file),Files.readAllBytes(file));
                } else {
                    CreateRawRequest(clientOutput,statusCode,statusMsg,"text/html","We're sorry, your webpage is in another castle!".getBytes());
                }
            } else {
                CreateRawRequest(clientOutput,statusCode,statusMsg,"text/html","We're sorry, your webpage exploded!".getBytes());
            }
            clientOutput.write("\r\n\r\n".getBytes());
            clientOutput.flush();
            client.close();
            System.out.println("Sent "+file+" to client "+client+".");
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}