AES128 CBC mode in Java, Kotlin and Ruby

Crypt.java

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import java.util.Base64;

public class Encryptor {
    public static String encrypt(String key, String initVector, String value) {
        try {
            Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5PADDING");
            IvParameterSpec iv = new IvParameterSpec(initVector.getBytes("UTF-8"));

            SecretKeySpec skeySpec = new SecretKeySpec(key.getBytes("UTF-8"), "AES");
            cipher.init(Cipher.ENCRYPT_MODE, skeySpec, iv);

            byte[] encrypted = cipher.doFinal(value.getBytes());
            String s = new String(Base64.getEncoder().encode(encrypted));
            return s;
        } catch (Exception ex) {
            ex.printStackTrace();
        }
        return null;
    }

    public static String decrypt(String key, String initVector, String encrypted) {
        try {
            IvParameterSpec iv = new IvParameterSpec(initVector.getBytes("UTF-8"));
            SecretKeySpec skeySpec = new SecretKeySpec(key.getBytes("UTF-8"), "AES");

            Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5PADDING");
            cipher.init(Cipher.DECRYPT_MODE, skeySpec, iv);

            byte[] original = cipher.doFinal(Base64.getDecoder().decode(encrypted));

            return new String(original);
        } catch (Exception ex) {
            ex.printStackTrace();
        }

        return null;
    }

    public static void main(String[] args) {
        String key = "Bar12345Bar12346"; // 128 bit key
        String initVector = "RandomInitVector"; // 16 bytes IV

        System.out.println(encrypt(key, initVector, "Hello World"));
        System.out.println(decrypt(key, initVector, encrypt(key, initVector, "Hello World")));
    }
}

Crypt.kt

import Encryptor.decrypt
import Encryptor.encrypt
import java.util.*
import javax.crypto.Cipher
import javax.crypto.spec.SecretKeySpec
import javax.crypto.spec.IvParameterSpec

object Encryptor {
    fun encrypt(key: String, initVector: String, value: String): String? {
        try {
            val cipher = Cipher.getInstance("AES/CBC/PKCS5PADDING")
            val iv = IvParameterSpec(initVector.toByteArray(charset("UTF-8")))

            val skeySpec = SecretKeySpec(key.toByteArray(charset("UTF-8")), "AES")
            cipher.init(Cipher.ENCRYPT_MODE, skeySpec, iv)

            val encrypted = cipher.doFinal(value.toByteArray())

            return String(Base64.getEncoder().encode(encrypted))
        } catch (ex: Exception) {
            ex.printStackTrace()
        }

        return null
    }

    fun decrypt(key: String, initVector: String, encrypted: String?): String? {
        try {
            val iv = IvParameterSpec(initVector.toByteArray(charset("UTF-8")))
            val skeySpec = SecretKeySpec(key.toByteArray(charset("UTF-8")), "AES")

            val cipher = Cipher.getInstance("AES/CBC/PKCS5PADDING")
            cipher.init(Cipher.DECRYPT_MODE, skeySpec, iv)

            val original = cipher.doFinal(Base64.getDecoder().decode(encrypted))

            return String(original)
        } catch (ex: Exception) {
            ex.printStackTrace()
        }

        return null
    }



}

fun main() {
    val key = "Bar12345Bar12346" // 128 bit key
    val initVector = "RandomInitVector" // 16 bytes IV

    println(encrypt(key, initVector, "Hello world!"))
    println(decrypt(key, initVector, encrypt(key, initVector, "Hello world!")))
}

Crypt.rb

require "openssl"
require "base64"
require 'byebug'

include Base64

plain_text = "Hello world!"

cipher = OpenSSL::Cipher::AES128.new(:CBC)
cipher.encrypt
key = "Bar12345Bar12346"
iv = "RandomInitVector"
cipher.key = key
cipher.iv = iv
cipher_text = cipher.update(plain_text) + cipher.final

cipher = OpenSSL::Cipher::AES128.new(:CBC)
cipher.decrypt
cipher.key = key
cipher.iv = iv
decrypted_plain_text = cipher.update(cipher_text) + cipher.final

puts "AES128 in CBC mode"
#puts "Key: " + urlsafe_encode64(key)
#puts "Iv: " + urlsafe_encode64(iv)
puts "Plain text: " + plain_text
puts "Cipher text: " + urlsafe_encode64(cipher_text)
puts "Decrypted plain text: " + decrypted_plain_text