AndroidでAESの暗号化する

import javax.crypto.*;
import java.security.KeyFactory;
import java.security.Key;
import java.security.spec.X509EncodedKeySpec;
import java.security.GeneralSecurityException;
import java.security.InvalidKeyException;
import java.security.spec.InvalidKeySpecException;
import java.security.NoSuchAlgorithmException;
import java.security.InvalidAlgorithmParameterException;
import java.security.spec.AlgorithmParameterSpec;
import android.util.Base64;
import java.io.InputStream;
import java.util.Random;

public class HogeCipher{
    private static final String keyString = "aaaabbbbccccddddaaaabbbbccccdddd"; //固定でもつ
    
    public String encryptString(String ivString, String input)
	throws
	    java.io.UnsupportedEncodingException,
	    NoSuchAlgorithmException,
	    NoSuchPaddingException,
	    InvalidKeyException,
	    InvalidAlgorithmParameterException,
	    IllegalBlockSizeException,
	    BadPaddingException{
	byte[] ivBytes = ivString.getBytes("UTF-8");
	byte[] keyBytes = this.keyString.getBytes("UTF-8");
	
	return Base64.encodeToString(this.encryptAES(ivBytes, keyBytes, input.getBytes("UTF-8")), Base64.DEFAULT);
    }
    
    public byte[] encryptAES(byte[] iv, byte[] key, byte[] enc)
	throws
	    NoSuchAlgorithmException,
	    NoSuchPaddingException,
	    InvalidKeyException,
	    InvalidAlgorithmParameterException,
	    IllegalBlockSizeException,
	    BadPaddingException{
	AlgorithmParameterSpec ivSpec = new IvParameterSpec(iv);
	SecretKeySpec newKey = new SecretKeySpec(key, "AES");
	Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
	cipher.init(Cipher.ENCRYPT_MODE, newKey, ivSpec);
	
	return cipher.doFinal(enc);
    }
    
    public byte[] decryptAES(byte[] iv, byte[] key, byte[] dec)
	throws
	    NoSuchAlgorithmException,
	    NoSuchPaddingException,
	    InvalidKeyException,
	    InvalidAlgorithmParameterException,
	    IllegalBlockSizeException,
	    BadPaddingException{
	AlgorithmParameterSpec ivSpec = new IvParameterSpec(iv);
	SecretKeySpec newKey = new SecretKeySpec(key, "AES");
	Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
	cipher.init(Cipher.DECRYPT_MODE, newKey);
	
	return cipher.doFinal(dec);
    }
}

動作確認はしていない