code: public void returnClient(CloseableHttpResponse resp) {
          try { 
              if (resp != null) {
                  EntityUtils.consume(resp.getEntity());
              }
          } catch (IOException ex) {
              //TODO: Could not consume response completely. This is serious because the client will not be returned back to pool.
              log.error("Error returning client to pool {}", ExceptionUtils.getStackTrace(ex));
          }
      }
docs: This ensures the response body is completely consumed and hence the HttpClient
  object will be return back to the pool successfully.
  @param resp