public void something() {
    String userName = "username";
    String password = "password";
    LdapContext ctx = null;
     try {
         Hashtable<String, String> env = new Hashtable<String, String>();
         env.put(Context.INITIAL_CONTEXT_FACTORY,
                 "com.sun.jndi.ldap.LdapCtxFactory");
         env.put(Context.SECURITY_AUTHENTICATION, "Simple");
         env.put(Context.SECURITY_PRINCIPAL, userName+"@something.net");
         env.put(Context.SECURITY_CREDENTIALS,password);
         env.put(Context.PROVIDER_URL, "some url");
         ctx = new InitialLdapContext(env, null);
}