private static String bytesToHex(byte[] bytes, char[] hexChars) {
        int v;
        for (int j = 0; j < bytes.length; j++) {
            v = bytes[j] & 0xFF;
            hexChars[j * 2] = HEX_CHAR_ARRAY[v >>> 4];
            hexChars[j * 2 + 1] = HEX_CHAR_ARRAY[v & 0x0F];
        }
        return new String(hexChars);
    }
Returns the hex string of the given byte array representing a SHA1 hash.
core/src/main/java/com/bumptech/glide/util/Util.java