LoginRolesServlet.java

package enterprise.programmatic_login;

import java.io.*;
import java.net.*;
import javax.annotation.security.DeclareRoles;
import javax.servlet.*;
import javax.servlet.http.*;

/**
 * Copied from https://docs.oracle.com/javaee/6/tutorial/doc/gjiie.html
 */
@DeclareRoles("javaee6user")
public class LoginRolesServlet extends HttpServlet {

    /** 
     * Processes requests for both HTTP GET and POST methods.
     * @param request servlet request
     * @param response servlet response
     */
    protected void processRequest(HttpServletRequest request, 
                 HttpServletResponse response)
            throws ServletException, IOException {
        response.setContentType("text/html;charset=UTF-8");
        PrintWriter out = response.getWriter();
        try {
            String userName = request.getParameter("txtUserName");
            String password = request.getParameter("txtPassword");
            
            out.println("Before Login" + "<br><br>");
            out.println("IsUserInRole?.." 
                        + request.isUserInRole("javaee6user")+"<br>");
            out.println("getRemoteUser?.." + request.getRemoteUser()+"<br>");
            out.println("getUserPrincipal?.." 
                        + request.getUserPrincipal()+"<br>");
            out.println("getAuthType?.." + request.getAuthType()+"<br><br>");
            
            try {
                request.login(userName, password); 
            } catch(ServletException ex) {
                out.println("Login Failed with a ServletException.." 
                    + ex.getMessage());
                return;
            }
            out.println("After Login..."+"<br><br>");
            out.println("IsUserInRole?.." 
                        + request.isUserInRole("javaee6user")+"<br>");
            out.println("getRemoteUser?.." + request.getRemoteUser()+"<br>");
            out.println("getUserPrincipal?.." 
                        + request.getUserPrincipal()+"<br>");
            out.println("getAuthType?.." + request.getAuthType()+"<br><br>");
            
            request.logout();
            out.println("After Logout..."+"<br><br>");
            out.println("IsUserInRole?.." 
                        + request.isUserInRole("javaee6user")+"<br>");
            out.println("getRemoteUser?.." + request.getRemoteUser()+"<br>");
            out.println("getUserPrincipal?.."
                        + request.getUserPrincipal()+"<br>");
            out.println("getAuthType?.." + request.getAuthType()+"<br>");
        } finally {
            out.close();
        }
    }
    //...
}