private boolean responseShouldContainEntity(final HttpRequest request, final HttpCacheEntry cacheEntry) {
        return Method.GET.isSame(request.getMethod()) && cacheEntry.getResource() != null;
    }
Generate a 304 - Not Modified response from the {@link HttpCacheEntry}. This should be
used to respond to conditional requests, when the entry exists or has been re-validated.
httpclient5-cache/src/main/java/org/apache/hc/client5/http/impl/cache/CachedHttpResponseGenerator.java