@Override
            public void completed(final T result) {
                if (consumer != null) {
                    consumer.accept(result);
                }
                latch.countDown();
            }
Generates a response body with random content.
 @param nbytes length of the desired response body
 @return an {@link HttpEntity}
httpclient5-cache/src/test/java/org/apache/hc/client5/http/impl/cache/HttpTestUtils.java