import javax.crypto.*;
import javax.crypto.spec.*;
import java.nio.charset.*;
import java.util.*;

public class Main {

    private static final String KEY = "u12hUPtyGhg5WR3t";

    public static void main(String[] args) throws Exception {
        var value1 = encryptAES("Mupi.123");
        var value2 = decryptAES(value1);

        System.out.println(value1);
        System.out.println(value2);
    }

    public static String encryptAES(String value) {
        try {
            SecretKey secretKey = new SecretKeySpec(getKeyBytes(), "AES");
            IvParameterSpec iv = new IvParameterSpec(getKeyBytes());

            Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
            cipher.init(Cipher.ENCRYPT_MODE, secretKey, iv);

            byte[] encrypted = cipher.doFinal(value.getBytes());

            return Base64.getEncoder().encodeToString(encrypted);
        } catch (Exception ex) {
            ex.printStackTrace();
        }

        return null;
    }

    public static String decryptAES(String encrypted) {
        try {
            SecretKey secretKey = new SecretKeySpec(getKeyBytes(), "AES");
            IvParameterSpec iv = new IvParameterSpec(getKeyBytes());

            Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
            cipher.init(Cipher.DECRYPT_MODE, secretKey, iv);

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

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

        return null;
    }

    public static byte[] getKeyBytes() {
        byte[] iv = new byte[16];
        return KEY.getBytes(StandardCharsets.UTF_8);
    }
}