java servlets resources jetty getresource

Jetty servlet override extension reading file

I'm trying to make a servlet on Jetty that overrides a file extension but that still needs to read the file being accessed.
I've been trying with resources but I could achieve nothing yet. I've tryed this code so far and, as you'll see, the resources are there but I somehow can't access them:

package valarionch.lab0.webapp.todo;

import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

@SuppressWarnings("serial")
@WebServlet(urlPatterns = { "*.ToDo" })
public class ToDoHandler extends HttpServlet {

@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp)
        throws ServletException, IOException {
    resp.setContentType("text/html");
    String s = req.getParameter("s");
    boolean small = (s != null && s.equals("1"));
    PrintWriter out = resp.getWriter();

    if (!small) {
        out.println("<html><head><title>ToDo list</title></head>"
                + "<body>");
    }

    for (String res : getServletContext().getResourcePaths("/")) {
        System.out.println("Resource: " + res);
        System.out.println("ResourceURL: " + getServletContext().getResource(res));
        System.out.println("ResourceStream: " + getServletContext().getResourceAsStream(res));
    }


    InputStream input = getServletContext().getResourceAsStream(req.getRequestURI());
    System.out.println(input);

    ToDoFormatter.parse(input, out, req.getParameter("q"));

    if (!small) {
        out.println("</body></html>");
    }
}

@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp)
        throws ServletException, IOException {
    doGet(req, resp);
}
}

this code prints this:

Resource: /META-INF/
ResourceURL: null
ResourceStream: null
Resource: /WEB-INF/
ResourceURL: null
ResourceStream: null
Resource: /index.html
ResourceURL: null
ResourceStream: null
Resource: /ToDoList.ToDo
ResourceURL: null
ResourceStream: null
null

I tryed with the next code too but also didn't worked:

getClass().getClassLoader().getResource(".").toString()+"../.."+req.getRequestURI()

so getClass().getClassLoader().getResource(".").toString() goes to WEB-INF/classess and +"../.."+req.getRequestURI() picks the actual file.

Am I missing something about how resources work? Is there another way to read the file?

Solution

You can use getServletContext().getRealPath() for such task. Let's imagine that you have the file myText.txt in the webapps folder:

   @SuppressWarnings("serial")
   @WebServlet(urlPatterns = { "*.ToDo" })
   public class UseGetRealPath extends HttpServlet {
    public void doGet( HttpServletRequest req, HttpServletResponse res )
      throws ServletException, IOException {
     String todoFile = getServletContext().getRealPath("/myText.txt");
     FileReader fr = new FileReader( todoFile );
     for( int c = fr.read(); c != -1; c = fr.read() ) {
      System.out.print( (char) c );
     }
     fr.close();
     res.getWriter().println( "check the console!" );
    }
   }

The code will open the file and dump its content in the console.