public Principal authenticate(String username,
    String credentials) 
{
        UniAddress machine;
        String host;
        host = Util.GetDCName(domain).replace('\\", ' ").trim();
        log("Authenticating against host " + host);
        NtlmPasswordAuthentication auth = new NtlmPasswordAuthentication(domain, username, credentials);
        try {
            machine = UniAddress.getByName(host);
            log("Authenticating against address " + machine);
        } catch(java.net.UnknownHostException e) {
            log("Exception finding domain controller", e);
            return null;
        }
        try {
            SmbSession.logon(machine, auth);
            return new NTDCPrincipal(this, username, credentials);
        } catch(jcifs.smb.SmbException e) {
            log("Exception logging onto domain controller", e);
            return null;
        }
}

 public String getDomain() 
{
       
        return domain;
}

 protected String getName() 
{
        return this.name;
}

 protected String getPassword(String username) 
{
        return null;
}

 protected Principal getPrincipal(String username) 
{
        return null;
}

 public boolean hasRole(Principal principal,
    String role) 
{
        if ((principal == null) ||
            (role == null) ||
            !(principal instanceof NTDCPrincipal))
            return (false);
        NTDCPrincipal ntdcPrincipal = (NTDCPrincipal) principal;
        if (!(ntdcPrincipal.getRealm() == this))
            return (false);
        boolean result = ntdcPrincipal.hasRole(role);
        if (debug  >= 2) {
            String name = principal.getName();
            if (result)
                log("NTDCRealm.hasRoleSuccess " + name + " : " + role);
            else
                log("NTDCRealm.hasRoleFailure " + name + " : " + role);
        }
        return (result);
}

 public  void setDomain(String newValue) 
{
        domain = newValue;
}