How do I serve external css, jpg and gif files fro

In index.html, External css is used and paths to image src are used to request css images from a folder. However the images are not loaded and css style is not applied to the page.

import java.io.*;
import java.util.*;

/**
 * An example of subclassing NanoHTTPD to make a custom HTTP server.
 */
public class HelloServer extends NanoHTTPD
{
    public HelloServer() throws IOException
    {
        super(8080, new File("."));
    }

    public Response serve(String uri, String method, Properties header, Properties parms, Properties files) {

        BufferedReader br = null;
        String msg="";

        try {

            String sCurrentLine;

            br = new BufferedReader(new FileReader("index.html"));

            while ((sCurrentLine = br.readLine()) != null) {
                //System.out.println(sCurrentLine);
                msg = msg + sCurrentLine;
                System.out.println(sCurrentLine);
            }

        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                if (br != null)br.close();
            } catch (IOException ex) {
                ex.printStackTrace();
            }
        }
        return new NanoHTTPD.Response( HTTP_OK, MIME_HTML, msg );
    }


    public static void main( String[] args )
    {
        try
        {
            new HelloServer();
        }
        catch( IOException ioe )
        {
            System.err.println( "Couldn't start server:\n" + ioe );
            System.exit( -1 );
        }
        System.out.println( "Listening on port 8080. Hit Enter to stop.\n" );
        try { System.in.read(); } catch( Throwable t ) {};
    }
}

In index.html, External css is used and paths to image src are used to request images from a folder but. However the images are not loaded and css style is not applied to the page.

Once you send back the HTML file, the browser will run though and make subsequent requests for the other resources - images, JS files, CSS, etc. What you will need to do is look at the "uri" parameter and that will tell you which file you need to send back to the client. Instead of hard-coding "index.html" you will need to base the filename off what is being requested.