static  void associateSecurityInformation(Object principal,
    Object credentials) 
{
      Principal securityPrincipal;
      // See if the principal is a Principal or String
      if( principal instanceof Principal )
      {
         securityPrincipal = (Principal) principal;
      }
      else
      {
         // Simply convert this to a name using toString
         String username = principal.toString();
         securityPrincipal = new SimplePrincipal(username);
      }
      // Associate this security context
      SecurityAssociationActions.setPrincipalInfo(securityPrincipal, credentials);
}

 public Context getInitialContext(Hashtable env) throws NamingException 
{
      Class[] interfaces = {Naming.class};
      Interceptor[] interceptors;
      Naming naming;
      // Get the login principal and credentials from the JNDI env
      Object credentials = env.get(Context.SECURITY_CREDENTIALS);
      Object principal = env.get(Context.SECURITY_PRINCIPAL);
      Object protocol = env.get(Context.SECURITY_PROTOCOL);
      if (principal != null && credentials != null)
      {
         if (protocol != null)
         {
            login(principal, credentials, protocol);
         }
         else
         {
            associateSecurityInformation(principal, credentials);
         }
         Interceptor[] tmp = {IsLocalInterceptor.singleton, SecurityClientInterceptor.singleton, InvokeRemoteInterceptor.singleton};
         interceptors = tmp;
      }
      else
      {
         Interceptor[] tmp = {IsLocalInterceptor.singleton, InvokeRemoteInterceptor.singleton};
         interceptors = tmp;
      }
      if (NamingContext.localServer != null) return new NamingContext(env, null, NamingContext.localServer);
      String providerUrl = (String) env.get(Context.PROVIDER_URL);
      if (providerUrl == null)
      {
         throw new RuntimeException("PROVIDER_URL not provided in jndi.properties.  Automatic discovery not implemented yet.");
      }
      try
      {
         naming = (Naming) Remoting.createPojiProxy("JNDI", interfaces, providerUrl, interceptors);
      }
      catch (Exception e)
      {
         throw new RuntimeException("Unable to create Naming proxy", e);
      }
      return new NamingContext(env, null, naming);
}

 public Object getObjectInstance(Object obj,
    Name name,
    Context nameCtx,
    Hashtable environment) throws Exception 
{
      Context ctx = getInitialContext(environment);
      Reference ref = (Reference) obj;
      return ctx.lookup((String) ref.get("URL").getContent());
}

 static  void login(Object principal,
    Object credentials,
    Object prop) throws AuthenticationException 
{
      String protocol = prop.toString();
      try
      {
         // Get the principal username
         String username;
         if( principal instanceof Principal )
         {
            Principal p = (Principal) principal;
            username = p.getName();
         }
         else
         {
            username = principal.toString();
         }
         UsernamePasswordHandler handler = new UsernamePasswordHandler(username,
            credentials);
         // Do the JAAS login
         LoginContext lc = new LoginContext(protocol, handler);
         lc.login();
      }
      catch(LoginException e)
      {
         AuthenticationException ex = new AuthenticationException("Failed to login using protocol="+protocol);
         ex.setRootCause(e);
         throw ex;
      }
}