public File getCacheFile(String url) {
        File cacheDir = config.cacheRoot;
        String fileName = config.fileNameGenerator.generate(url);
        return new File(cacheDir, fileName);
    }
Checks is cache contains fully cached file for particular url.

@param url an url cache file will be checked for.
@return {@code true} if cache contains fully cached file for passed in parameters url.
VideoCache/src/main/java/com/yc/videocache/HttpProxyCacheServer.java