使用bouncycastle进行加密
BouncyCastle是一个开源的加解密解决方案，主页在http://www.bouncycastle.org/,下面写一个工具类对String加密和解密
/** * use bouncycastle to AES encrypt */public class AESUtils {private static final AESUtils instance = new AESUtils();byte[] iv = { 0x38, 0x37, 0x36, 0x35, 0x34, 0x33, 0x32, 0x31, 0x38, 0x37,0x36, 0x35, 0x34, 0x33, 0x32, 0x31 };byte[] keybytes = { 0x70, 0x2F, 0x17, 0x7F, 0x6C, 0x3A, 0x22, 0x11, 0x3F,0x44, 0x5A, 0x66, 0x77, 0x1A, 0x12, 0x1C };private AESUtils() {}public static AESUtils getInstance() {return instance;}private Key key;private byte[] enc;public String encrypt(String msg) {String str;try {Security.addProvider(new BouncyCastleProvider());key = new SecretKeySpec(keybytes, "AES");Cipher in = Cipher.getInstance("AES/CBC/PKCS7Padding", "BC");in.init(Cipher.ENCRYPT_MODE, key, new IvParameterSpec(iv));enc = in.doFinal(msg.getBytes());str = new String(Hex.encode(enc));return str;} catch (InvalidKeyException e) {e.printStackTrace();} catch (NoSuchAlgorithmException e) {e.printStackTrace();} catch (NoSuchProviderException e) {e.printStackTrace();} catch (NoSuchPaddingException e) {e.printStackTrace();} catch (InvalidAlgorithmParameterException e) {e.printStackTrace();} catch (IllegalBlockSizeException e) {e.printStackTrace();} catch (BadPaddingException e) {e.printStackTrace();}return null;}public String decrypt(byte[] msg) {String str;try { Security.addProvider(new BouncyCastleProvider());key = new SecretKeySpec(keybytes, "AES");Cipher out = Cipher.getInstance("AES/CBC/PKCS7Padding", "BC");out.init(Cipher.DECRYPT_MODE, key, new IvParameterSpec(iv));byte[] dec = out.doFinal(msg);str = new String(dec);return str;} catch (InvalidKeyException e) {e.printStackTrace();} catch (NoSuchAlgorithmException e) {e.printStackTrace();} catch (NoSuchProviderException e) {e.printStackTrace();} catch (NoSuchPaddingException e) {e.printStackTrace();} catch (InvalidAlgorithmParameterException e) {e.printStackTrace();} catch (IllegalBlockSizeException e) {e.printStackTrace();} catch (BadPaddingException e) {e.printStackTrace();}return null;}}?