kotlin md5 to hex

calcHash.kt

    private fun File.calcHash(algorithm: String = "MD5", bufferSize: Int = 1024): String {
        this.inputStream().use { input ->
            val buffer = ByteArray(bufferSize)
            val digest = MessageDigest.getInstance(algorithm)

            read@ while (true) {
                when (val bytesRead = input.read(buffer)) {
                    -1 -> break@read
                    else -> digest.update(buffer, 0, bytesRead)
                }
            }
            return digest.digest().toHexString()
        }
    }

    private fun ByteArray.toHexString(): String {
        return this.fold(StringBuilder()) { result, b -> result.append(String.format("%02X", b)) }.toString().toUpperCase()
    }