AesCryptoUtil.kt

/**
 * @author indrajit
 */
class AesCryptoUtil(secret: String) {
    private val secretKey: SecretKeySpec

    init {
        var key: ByteArray = secret.toByteArray(StandardCharsets.UTF_8)
        val sha = MessageDigest.getInstance("SHA-1")
        key = sha.digest(key)
        key = key.copyOf(16)
        secretKey = SecretKeySpec(key, "AES")
    }

    fun encrypt(strToEncrypt: String): String {
        val cipher = Cipher.getInstance(AES_TRANSFORMATION)
        cipher.init(Cipher.ENCRYPT_MODE, secretKey)
        return Base64.getEncoder().encodeToString(cipher.doFinal(strToEncrypt.toByteArray(StandardCharsets.UTF_8)))
    }

    fun decrypt(strToDecrypt: String): String {
        val cipher = Cipher.getInstance(AES_TRANSFORMATION)
        cipher.init(Cipher.DECRYPT_MODE, secretKey)
        return String(cipher.doFinal(Base64.getDecoder().decode(strToDecrypt)))
    }

    companion object {
        private const val AES_TRANSFORMATION = "AES/ECB/PKCS5Padding"
    }
}