docs: protected File getFile(String imageUri) {
  		String fileName = fileNameGenerator.generate(imageUri);
  		File dir = cacheDir;
  		if (!cacheDir.exists() && !cacheDir.mkdirs()) {
  			if (reserveCacheDir != null && (reserveCacheDir.exists() || reserveCacheDir.mkdirs())) {
  				dir = reserveCacheDir;
  			}
  		}
  		return new File(dir, fileName);
  	}