@Override
  protected void addHttpAuthHeader(HttpRequest httpRequest, HttpContext httpContext)
    throws Exception {
    httpRequest.addHeader(HIVE_DELEGATION_TOKEN_HEADER, tokenStr);
  }
The class is instantiated with the username and password, it is then
used to add header with these credentials to HTTP requests
jdbc/src/java/org/apache/hive/jdbc/HttpTokenAuthInterceptor.java