[jetty-users] Jetty 9 bug

[Denis Bardadym <bardadymchik@xxxxxxxxx>]

Hello.

I found that jetty 9.0.2.v20130417 HttpServletRequest.getHeader return null when header is empty. You can see this in simple application:

import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.eclipse.jetty.server.Server;
import org.eclipse.jetty.servlet.ServletHandler;
 
public class MinimalServlets {
 
    public static void main(String[] args) throws Exception {
        Server server = new Server(8080);
        ServletHandler handler = new ServletHandler();
        server.setHandler(handler);
        handler.addServletWithMapping(HelloServlet.class, "/*");
        server.start();
        server.join();
    }
 
    public static class HelloServlet extends HttpServlet {
 
        @Override
        protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
            response.setContentType("text/html");
            response.setStatus(HttpServletResponse.SC_OK);
            java.io.Writer w = response.getWriter();
            w.println(request.getHeader("User-Agent"));
            w.println(request.getHeader("X-Not-Exists"));
        }
    }
}

When i send curl request like this:

mac:liftweb den$ curl -v -D - -H "User-Agent;" -H "User-Agent:" http://localhost:8080
* About to connect() to localhost port 8080 (#0)
*   Trying ::1...
* connected
* Connected to localhost (::1) port 8080 (#0)
> GET / HTTP/1.1
> Host: localhost:8080
> Accept: */*
> User-Agent:
> 
< HTTP/1.1 200 OK
HTTP/1.1 200 OK
< Content-Type: text/html; charset=ISO-8859-1
Content-Type: text/html; charset=ISO-8859-1
< Transfer-Encoding: chunked
Transfer-Encoding: chunked
< Server: Jetty(9.0.2.v20130417)
Server: Jetty(9.0.2.v20130417)

< 
null
null
* Connection #0 to host localhost left intact
* Closing connection #0

It returns both nulls. But by javadoc it should return null only if header not presented but you see that User-Agent: just empty.

This does not happen in jetty8:

@SuppressWarnings("serial")
public class HelloServlet extends HttpServlet
{
    String greeting = "Hello";

    public HelloServlet()
    {
    }

    public HelloServlet(String hi)
    {
        greeting = hi;
    }

    private String getVal(String s) {
        if(s == null) return "null";
        else return s;
    }

    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException
    {
        response.setContentType("text/html");
        response.setStatus(HttpServletResponse.SC_OK);
        PrintWriter writer = response.getWriter();
        writer.println("User-Agent: " + getVal(request.getHeader("User-Agent")));
        writer.println("X-Not-Exists: " + getVal(request.getHeader("X-Not-Exists")));
        writer.flush();
        writer.close();
    }
}

and
public class OneServletContext {
    public static void main(String[] args) throws Exception {
        Server server = new Server(8080);

        ServletContextHandler context = new ServletContextHandler(ServletContextHandler.SESSIONS);
        context.setContextPath("/");
        server.setHandler(context);

        // Server content from tmp
        ServletHolder holder = context.addServlet(org.eclipse.jetty.servlet.DefaultServlet.class, "/tmp/*");
        holder.setInitParameter("resourceBase", "/tmp");
        holder.setInitParameter("pathInfoOnly", "true");

        // Serve some hello world servlets
        context.addServlet(new ServletHolder(new HelloServlet()), "/*");
        context.addServlet(new ServletHolder(new HelloServlet("Buongiorno Mondo")), "/it/*");
        context.addServlet(new ServletHolder(new HelloServlet("Bonjour le Monde")), "/fr/*");

        server.start();
        server.join();
    }
}

so when i send it request:

mac:liftweb den$ curl -v -D - -H "User-Agent;" -H "User-Agent:" http://localhost:8080
* About to connect() to localhost port 8080 (#0)
*   Trying ::1...
* connected
* Connected to localhost (::1) port 8080 (#0)
> GET / HTTP/1.1
> Host: localhost:8080
> Accept: */*
> User-Agent:
> 
< HTTP/1.1 200 OK
HTTP/1.1 200 OK
< Content-Type: text/html;charset=ISO-8859-1
Content-Type: text/html;charset=ISO-8859-1
< Transfer-Encoding: chunked
Transfer-Encoding: chunked
< Server: Jetty(8.1.10.v20130312)
Server: Jetty(8.1.10.v20130312)

< 
User-Agent: 
X-Not-Exists: null
* Connection #0 to host localhost left intact
* Closing connection #0


Does it really bug??

Thanks, Denis Bardadym.