Custom Authentication Filter

package com.pankaj.filters;

import javax.security.auth.Subject;
import javax.security.auth.login.LoginException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.ibm.portal.auth.ExplicitLoginFilter;
import com.ibm.portal.auth.ExplicitLoginFilterChain;
import com.ibm.portal.auth.FilterChainContext;
import com.ibm.portal.auth.exceptions.AuthenticationException;
import com.ibm.portal.auth.exceptions.AuthenticationFailedException;
import com.ibm.portal.auth.exceptions.PasswordInvalidException;
import com.ibm.portal.auth.exceptions.SystemLoginException;
import com.ibm.portal.auth.exceptions.UserIDInvalidException;

/**
 * @author Pankaj Gupta
 * build path dependency
 * 1. C:/IBM/WebSphere/PortalServer/base/wp.auth.base/shared/app/wp.auth.base.jar
 * 2. C:/IBM/WebSphere/PortalServer/base/wp.auth.cmd/shared/app/wp.auth.cmd.jar
 *
 */
public class CustomExplicitLoginFilter implements ExplicitLoginFilter {

 Context context = null;
 PumaHome pumaHome = null;

    public CustomExplicitLoginFilter() {
        super();

    }

    public void init(SecurityFilterConfig filterConfig) throws SecurityFilterInitException {
        System.out.println("Entering com.pankaj.filters.CustomExplicitLoginFilter.init(...)");
     try{
      context = new InitialContext();
   pumaHome = (PumaHome) context.lookup(com.ibm.portal.um.PumaHome.JNDI_NAME);
     } catch (Exception exp){
      exp.printStackTrace();
     }
        System.out.println("Exiting com.pankaj.filters.CustomExplicitLoginFilter.init(...)");
    }

    public void login(HttpServletRequest req, HttpServletResponse resp, String userID, char password[],
            FilterChainContext portalLoginContext, Subject subject, String realm, ExplicitLoginFilterChain chain)
            throws LoginException, WSSecurityException, PasswordInvalidException, UserIDInvalidException,
            AuthenticationFailedException, AuthenticationException, SystemLoginException,
            com.ibm.portal.auth.exceptions.LoginException {

     long startTime = System.currentTimeMillis();

     long subTaskTime = startTime;

     System.out.println("Entering CustomExplicitLoginFilter.login() ... Time Taken : " + (System.currentTimeMillis() - startTime) + " milli seconds");

     chain.login(req, resp, userID, password, portalLoginContext, subject, realm);

     System.out.println("User Authenticated ... Time Taken : " + (System.currentTimeMillis() - subTaskTime) + " milli seconds");
     subTaskTime = System.currentTimeMillis();

     List groupList = this.getUserGroups(req);

     System.out.println("User groups retrieved ... Time Taken : " + (System.currentTimeMillis() - subTaskTime) + " milli seconds");
     subTaskTime = System.currentTimeMillis();

     if(this.isUserGroupAvailable(req, groupList, "wpsadmins") || this.isUserGroupAvailable(req, groupList, "wpadmins")){
            System.out.println("Group Checked ... Time Taken : " + (System.currentTimeMillis() - subTaskTime) + " milli seconds");
            subTaskTime = System.currentTimeMillis();
      portalLoginContext.setRedirectURL("/wps/myportal/Administration");
            System.out.println("URL created ... Time Taken : " + (System.currentTimeMillis() - subTaskTime) + " milli seconds");
            subTaskTime = System.currentTimeMillis();
     }
        System.out.println("Exiting CustomExplicitLoginFilter.login(...) ... Time Took : "
          + (System.currentTimeMillis() - startTime) + " milli seconds");
    }


    public void destroy() {
        // This is an empty implementation. No code required!!!
    }

    private List getUserGroups(HttpServletRequest request) {
     List groupList = null;
     try {
      PumaProfile pumaProfile = pumaHome.getProfile(request);
      com.ibm.portal.um.User user = pumaProfile.getCurrentUser();
      PumaLocator pl = pumaHome.getLocator(request);
      groupList = pl.findGroupsByPrincipal(user, false);
     } catch(Exception exp){
      exp.printStackTrace();
     }

     return groupList;
    }

 private boolean isUserGroupAvailable(HttpServletRequest request, List groupList, String userGroup) {
  boolean groupFlag = false;
     try {
      List attribs = new ArrayList();
      attribs.add("cn");
      PumaProfile pumaProfile = pumaHome.getProfile(request);
      for(Iterator group_itr = groupList.iterator();group_itr.hasNext();){
       Group group = (Group) group_itr.next();
       Map group_attribs = pumaProfile.getAttributes(group, attribs );
       String group_cn = (String) group_attribs.get((Object)"cn");
       System.out.println("group cn: " + group_cn);
       if(group_cn.equals(userGroup)){
         groupFlag = true;
         break;
       }
      }
     }
     catch (Exception exp) {
   exp.printStackTrace();
     }
  return groupFlag;
    }
}