AES enc/dec

import java.math.*;
import java.security.*;
import java.util.*;
import javax.crypto.*;
import javax.crypto.spec.*;

public class Test {
    private static Key key;

    public static void main(String... args) {
        key = getKey("1234567890$");
        byte[] encrypted = encrypt("test");
        String str = new String(encrypted);
        System.out.println("encrypt: "+str);
        System.out.println("decrypt arr: "+decrypt(encrypted));
        System.out.println("decrypt str: "+decrypt(stringFromBytes(toHex(str))));
    }

    public static byte[] stringFromBytes(String s) {
        byte[] byteArray = new byte[s.length()/2];
        String[] strBytes = new String[s.length()/2];
        int k = 0;
        for (int i = 0; i < s.length(); i=i+2) {
            int j = i+2;
            strBytes[k] = s.substring(i,j);
            byteArray[k] = (byte)Integer.parseInt(strBytes[k], 16);
            k++;
        }
        return byteArray;
    }

    private static String toHex(String s) {
        return String.format("%2x", new BigInteger(1, s.getBytes()));
    }

    private static String decrypt(byte[] enc) {
        try {
            Cipher cipher = Cipher.getInstance("AES");
            cipher.init(Cipher.DECRYPT_MODE, key);
            return new String(cipher.doFinal(enc));
        } catch (IllegalBlockSizeException | BadPaddingException | NoSuchPaddingException | NoSuchAlgorithmException | InvalidKeyException e) {}
        return null;
    }

    private static byte[] encrypt(String text) {
        try {
            Cipher cipher = Cipher.getInstance("AES");
            cipher.init(Cipher.ENCRYPT_MODE, key);
            return cipher.doFinal(text.getBytes());
        } catch (IllegalBlockSizeException | BadPaddingException | NoSuchPaddingException | NoSuchAlgorithmException | InvalidKeyException e) {}
        return null;
    }

    private static Key getKey(String pass) {
        if (pass != null && !pass.isEmpty())
            try {
                MessageDigest sha = MessageDigest.getInstance("SHA-1");
                byte[] key = pass.getBytes();
                key = sha.digest(key);
                key = Arrays.copyOf(key, 16);
                return new SecretKeySpec(key, "AES");
            } catch (NoSuchAlgorithmException e) {}
        return null;
    }
}