Java tutorial
import java.util.*; import java.io.*; import javax.servlet.*; import javax.servlet.http.*; import java.security.*; public class MyServlet extends HttpServlet { public void init(ServletConfig cfg) throws ServletException { super.init(cfg); } public void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException { response.setContentType("text/html"); PrintWriter out = response.getWriter(); out.println("<HTML>"); out.println("<HEAD>"); out.println("<TITLE>"); out.println("User Authentication"); out.println("</TITLE>"); out.println("</HEAD>"); out.println("<BODY>"); out.println("<H1>User Authentication</H1>"); String type = request.getAuthType(); out.println("Welcome to this secure page.<BR>"); out.println("Authentication mechanism: " + type + "<BR>"); Principal principal = request.getUserPrincipal(); out.println("Your username is: " + principal.getName() + "<BR>"); out.println("</BODY>"); out.println("</HTML>"); } }