/** * 加密工具类 *  * <pre> * AES支持128/192/256,取决于密钥长度(与位数对应) * DES密钥长度8字节 * 3DES密钥长度24字节 *  * 采用CBC 需指定初始向量IV，长度与分组大小相同 * DES为8字节；AES为16字节 *  * </pre> */public class Crypto {    static {        // add bouncycastle support for md4 etc..        Security.addProvider(new BouncyCastleProvider());    }    public static enum CryptType {        DES_ECB_PKCS5("DES/ECB/PKCS5Padding"),        DES_CBC_PKCS5("DES/CBC/PKCS5Padding", 8),        DESede_ECB_PKCS5("DESede/ECB/PKCS5Padding"),        DESede_CBC_PKCS5("DESede/CBC/PKCS5Padding", 8),        AES_ECB_PKCS5("AES/CBC/PKCS5Padding", 16),        AES_CBC_PKCS5("AES/CBC/PKCS5Padding", 16),        AES_CBC_PKCS7("AES/CBC/PKCS7Padding", 16);        public final String algorithm;        public final String keyAlg;        public final int ivlen;        private CryptType(String algorithm, int ivlen) {            this.algorithm = algorithm;            this.keyAlg = this.algorithm.substring(0, this.algorithm.indexOf(‘/‘));            this.ivlen = ivlen;        }        private CryptType(String algorithm) {            this(algorithm, 0);        }        @Override        public String toString() {            return this.algorithm;        }    }    /**     * Initialize the key     *      * @param type     * @return     */    public static String initKey(CryptType type) {        try {            KeyGenerator generator = KeyGenerator.getInstance(type.keyAlg);            SecretKey secretKey = generator.generateKey();            byte[] key = secretKey.getEncoded();            return Codec.byteToHexString(key);        } catch (Exception e) {            throw new RuntimeException(e);        }    }    /**     * generate default ivparam for type     *      * @return     */    public static byte[] generateDefaultIv(CryptType type) {        byte[] iv = new byte[type.ivlen];        for (int i = 0; i < iv.length; i++) {            iv[i] = 0x01;        }        return iv;    }    /**     * Encrypt the value with the encryption standard.     *      * @param value     *            raw string     * @param key     *            in hex format     * @param iv     *            in hex format if exist     * @param type     * @return result in hex format     */    public static String encrypt(String value, String key, String iv, CryptType type) {        byte[] dvalue;        try {            dvalue = value.getBytes("utf-8");        } catch (UnsupportedEncodingException e) {            throw new RuntimeException(e);        }        byte[] dkey = Codec.hexStringToByte(key);        byte[] div = null;        if (iv != null && iv.length() > 0) {            div = Codec.hexStringToByte(iv);        }        byte[] result = encrypt(dvalue, dkey, div, type);        return Codec.byteToHexString(result);    }    /**     * Encrypt the value with the encryption standard.     *      * <pre>     * key must have the corresponding length.     *      * if use cbc mode which need iv param, the iv must not be null,     * and iv data length is 16 for aes, 8 for des     *      * </pre>     *      * @param value     * @param key     * @param iv     * @return     */    public static byte[] encrypt(byte[] value, byte[] key, byte[] iv, CryptType type) {        try {            SecretKeySpec skeySpec = new SecretKeySpec(key, type.keyAlg);            Cipher cipher = Cipher.getInstance(type.algorithm);            IvParameterSpec ivparamSpec = null;            if (iv != null) {                ivparamSpec = new IvParameterSpec(iv);            }            cipher.init(Cipher.ENCRYPT_MODE, skeySpec, ivparamSpec);            return cipher.doFinal(value);        } catch (Exception ex) {            throw new RuntimeException(ex);        }    }    /**     * Encrypt the value with the encryption standard.     *      * @param value     *            encoded data in hex format     * @param key     *            in hex format     * @param iv     *            in hex format if exist     * @param type     * @return result raw string     */    public static String decrypt(String value, String key, String iv, CryptType type) {        byte[] dvalue =http://www.mamicode.com/ Codec.hexStringToByte(value);        byte[] dkey = Codec.hexStringToByte(key);        byte[] div = null;        if (iv != null && iv.length() > 0) {            div = Codec.hexStringToByte(iv);        }        byte[] result = decrypt(dvalue, dkey, div, type);        try {            return new String(result, "utf-8");        } catch (UnsupportedEncodingException e) {            throw new RuntimeException(e);        }    }    /**     * Decrypt the value with the encryption standard.     *      * <pre>     * key must have the corresponding length.     *      * if use cbc mode which need iv param, the iv must not be null,     * and iv data length is 16 for aes, 8 for des     *      * </pre>     *      * @param value     * @param key     * @param iv     * @param type     * @return     */    public static byte[] decrypt(byte[] value, byte[] key, byte[] iv, CryptType type) {        try {            SecretKeySpec skeySpec = new SecretKeySpec(key, type.keyAlg);            Cipher cipher = Cipher.getInstance(type.algorithm);            IvParameterSpec ivparamSpec = null;            if (iv != null) {                ivparamSpec = new IvParameterSpec(iv);            }            cipher.init(Cipher.DECRYPT_MODE, skeySpec, ivparamSpec);            return cipher.doFinal(value);        } catch (Exception ex) {            throw new RuntimeException(ex);        }    }}

Exception in thread "main" java.security.InvalidKeyException: Illegal key size or default parameters