bytekey | lexicographic sort-order preserving binary encoding | Hashing library

import java.nio.file.Files;
import java.nio.file.Paths;
import java.nio.charset.*;
import javax.crypto.*;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import java.io.IOException;
import java.util.Arrays;

import java.util.*;

public class AES {

    public static void main(String[] args) throws Exception {
        Scanner input = new Scanner(System.in);

        System.out.println("Enter your 16 character key here:");
        String EncryptionKey = input.next();
        byte[] iv = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
        IvParameterSpec ivspec = new IvParameterSpec(iv);

        KeyGenerator KeyGen = KeyGenerator.getInstance("AES");
        KeyGen.init(128);

        Cipher AesCipher = Cipher.getInstance("AES/CFB/NoPadding");
        System.out.println("Enter text to encrypt or decrypt:");
        String Text = input.next();

        System.out.println("Do you want to encrypt or decrypt (e/d)");
        String answer = input.next();
        if (answer.equalsIgnoreCase("e")) {

            byte[] byteKey = (EncryptionKey.getBytes());
            byte[] byteText = (Text).getBytes();
            SecretKeySpec secretKeySpec = new SecretKeySpec(byteKey, "AES");
            AesCipher.init(Cipher.ENCRYPT_MODE, secretKeySpec, ivspec);
            AesCipher.init(Cipher.ENCRYPT_MODE, secretKeySpec, ivspec); // ERROR LINE
            byte[] byteCipherText = AesCipher.doFinal(byteText);

            System.out.println(byteCipherText);

        } else if (answer.equalsIgnoreCase("d")) {

            byte[] byteKey = (EncryptionKey.getBytes());
            byte[] byteText = (Text).getBytes();
            String decryptKeyString = input.nextLine();
            Charset charset = StandardCharsets.UTF_16;
            byte[] cipherText = decryptKeyString.getBytes(charset);

            SecretKeySpec secretKeySpec = new SecretKeySpec(byteKey, "AES");
            AesCipher.init(Cipher.DECRYPT_MODE, secretKeySpec, ivspec); // ERROR LINE
            //byte[] bytePlainText = AesCipher.doFinal(cipherText);
            String plaintext = new String(AesCipher.doFinal(cipherText), "UTF-8");
            //Files.write(Paths.get(FileName2), bytePlainText);
            System.out.println(plaintext);
        }
    }

}