VariableClarity.java

public void buildThumbnailWithUrl() {
        final List<Thumbnail> rawThumbnailList = getThumbnailListFromSomeWhere();
        final String appropriateCdn = getTheRightCdnBasedOnRegion();
        final String defaultCdn = getDefaultCdn();

        final List<Thumbnail> thumbnailListWithCdn = rawThumbnailList.stream().map(eachThumbnail -> {
            final String cdnChose = eachThumbnail.isHasLarge() ? defaultCdn : appropriateCdn;
            eachThumbnail.setThumbnailUri(cdnChose + eachThumbnail.getThumbnailUri());
            return eachThumbnail;
        }).collect(Collectors.toList());

        final List<ThumbnailResponse> responseData = thumbnailListWithCdn.stream()
                .map(eachThumbnail -> ThumbnailResponse.builder().thumbnailUrl(eachThumbnail.getThumbnailUri()).build())
                .collect(Collectors.toList());
    }