@Test
public void testClose() throws IOException {

    CloseableHttpClient httpClient = Mockito.mock(CloseableHttpClient.class);
    HttpDriver httpDriver = new HttpDriver.Builder("", null, "asdf".toCharArray(), null, null)
            .build();
    httpDriver.setHttpClient(httpClient);
    httpDriver.close();
    httpDriver.setHttpClient(null);
    httpDriver.close();
}