public static File getPhotoCacheDir(Context context, String cacheName) {
        File cacheDir = context.getCacheDir();
        if (cacheDir != null) {
            File result = new File(cacheDir, cacheName);
            if (!result.mkdirs() && (!result.exists() || !result.isDirectory())) {
                // File wasn't able to create a directory, or the result exists but not a directory
                return null;
            }
            return result;
        }
        if (Log.isLoggable(TAG, Log.ERROR)) {
            Log.e(TAG, "default disk cache dir is null");
        }
        return null;
    }
Returns a directory with the given name in the private cache directory of the application to use to store
retrieved media and thumbnails.

@see #getPhotoCacheDir(Context)

@param context A context.
@param cacheName The name of the subdirectory in which to store the cache.
core/src/main/java/com/bumptech/glide/Glide.java