Example Code for Programmatic Security

The following code demonstrates the use of programmatic security for the purposes of programmatic login. This servlet does the following:

1. It displays information about the current user.

2. It prompts the user to log in.

3. It prints out the information again to demonstrate the effect of the login method.

4. It logs the user out.

5. It prints out the information again to demonstrate the effect of the logout method.

package enterprise.programmatic_login;

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

@DeclareRoles("javaee6user")
public class LoginServlet 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();
        }
    }
    ...
}