import java.security.MessageDigest
import java.util.*
import javax.crypto.Cipher
import javax.crypto.spec.IvParameterSpec
import javax.crypto.spec.SecretKeySpec

fun main(args: Array<String>) {
    val cipher = Cipher.getInstance("AES/CBC/PKCS5PADDING")
    val key = Arrays.copyOf(
            MessageDigest.getInstance("SHA-256").digest("secret key".toByteArray()), 16
    )
    val secretKeySpec = SecretKeySpec(key, "AES")
    val iv = Arrays.copyOf(
            MessageDigest.getInstance("SHA-256").digest("initialization vector".toByteArray()),
            16
    )
    val initVec = IvParameterSpec(iv)
    cipher.init(Cipher.ENCRYPT_MODE, secretKeySpec, initVec)
    val str = "My string to encrypt"
    val enc = cipher.doFinal(str.toByteArray())
    println(Base64.getEncoder().encodeToString(enc))
    cipher.init(Cipher.DECRYPT_MODE, secretKeySpec, initVec)
    val result = String(cipher.doFinal(enc))
    println(result)
}