com.jcorporate.expresso.core.servlet
Class CheckLogin

java.lang.Object
  com.jcorporate.expresso.core.servlet.CheckLogin

public final class CheckLogin

extends Object

CheckLogin accepts an HttpServletRequest and HttpServletResponse object pair, and attempts to check if the user is logged in. If not, CheckLogin tries to log the user in via a cookie from the client. If this is not possible, the user is logged in as "NONE". It has now been modified to be a Singleton Object rather than having a new object allocated with each request. Example Usage:
CheckLogin.getInstance().checkLogin(request,response);

Version:

$Revision: 1.20 $ $Date: 2003/08/03 10:26:26 $

Author:

Michael Nash, Singleton Modification by Michael Rimov

Constructor Summary

protected

CheckLogin() Default Constructor....

Method Summary

void	checkLogin(HttpServletRequest request, HttpServletResponse response) Constructor.
void	checkLogin(HttpServletRequest request, HttpServletResponse response, ServletConfig c) Enhanced Constructor.
void	checkLogin(HttpServletRequest request, HttpServletResponse response, ServletConfig c, String forceDB) Enhanced Constructor.
static CheckLogin	getInstance()
void	logInAsNone(HttpServletRequest request, String forceDB) For some reason a login session could not be established, so log the user in as the "unknown" user "NONE"
boolean	loginViaContainer(HttpServletRequest request, String forceDB) Try to log in with a user name obtained from the container.
boolean	loginViaCookie(HttpServletRequest request, String forceDB) Try to log in via the cookie from the client - if successful, return true.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

CheckLogin

protected CheckLogin()

Default Constructor.... Simply sets up the Log It should not be called anymore directly. Use getInstance() instead.

Method Detail

getInstance

public static CheckLogin getInstance()

checkLogin

public void checkLogin(HttpServletRequest request,
                       HttpServletResponse response,
                       ServletConfig c,
                       String forceDB)
                throws ServletException,
                       NonHandleableException,
                       IOException

Enhanced Constructor. Same as older constructor, but includes option to specify a particular database

Parameters:

request - Standard request object

response - Standard response object

c - ServletConfig object of the calling servlet

forceDB - the db to force a login to

Throws:

ServletException - If an uncaught exception occurs

IOException - If an I/O error occurs while communicating with the client

NonHandleableException - upon fatal error

checkLogin

public void checkLogin(HttpServletRequest request,
                       HttpServletResponse response,
                       ServletConfig c)
                throws ServletException,
                       NonHandleableException,
                       IOException

Enhanced Constructor. Same as older constructor, but also checks if this application is initialized, and initializes if needed

Parameters:

request - Standard request object

response - Standard response object

c - ServletConfig object of the calling servlet

Throws:

ServletException - If an uncaught exception occurs

IOException - If an I/O error occurs while communicating with the client

NonHandleableException - upon fatal error

checkLogin

public void checkLogin(HttpServletRequest request,
                       HttpServletResponse response)
                throws ServletException,
                       NonHandleableException,
                       IOException

Constructor. Performs all the functions of the class immediately

Parameters:

request - Standard request object

response - Standard response object

Throws:

ServletException - If an uncaught exception occurs

IOException - If an I/O error occurs while communicating with the client

NonHandleableException - upon fatal error

logInAsNone

public void logInAsNone(HttpServletRequest request,
                        String forceDB)
                 throws ServletException

For some reason a login session could not be established, so log the user in as the "unknown" user "NONE"

Parameters:

request - the servlet request object

forceDB - the data context to log into

Throws:

ServletException

loginViaContainer

public boolean loginViaContainer(HttpServletRequest request,
                                 String forceDB)
                          throws Exception

Try to log in with a user name obtained from the container. This function assumes that the container has already authenticated the user's ID and password, thus no password checking is performed. This is intended to allow more fine-grained access control via Expresso's built-in mechanisms. If successful, return true. If not, return false.

Parameters:

request - The request object

forceDB - Name of default database to set

Returns:

true if successfull

Throws:

Exception - upon error

loginViaCookie

public boolean loginViaCookie(HttpServletRequest request,
                              String forceDB)
                       throws Exception

Try to log in via the cookie from the client - if successful, return true. If not, return false

Parameters:

request - the servlet request object

forceDB - the data context to login to

Returns:

true if successfull

Throws:

Exception - upon error