MD5,sha1加密工具類

/**
     * 利用MD5加密
     * @return String  加密後的字符串
     * @param str  待加密的字符串
     * @throws NoSuchAlgorithmException   異常
     * @throws UnsupportedEncodingException  異常
     */
    @SuppressWarnings("finally")
    public String Md5(String str) {
        String newstr = "";
        //1.確定計算方式
        MessageDigest md5;
        try {
            md5 = MessageDigest.getInstance("MD5");
            BASE64Encoder base64Encoder=new BASE64Encoder();
            //2。加密後的字符串
            newstr = base64Encoder.encode(md5.digest(str.getBytes("utf-8")));
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }finally{
            return newstr;
        }
    }

/**
     * sha1加密
     * @param str 返回加密字符串
     * @return
     */
    public static String getSha1(String str) {
        if (str == null || str.length() == 0) {
            return null;
        }
        char hexDigits[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };
        try {
            MessageDigest mdTemp = MessageDigest.getInstance("SHA1");
            mdTemp.update(str.getBytes("UTF-8"));

            byte[] md = mdTemp.digest();
            int j = md.length;
            char buf[] = new char[j * 2];
            int k = 0;
            for (int i = 0; i < j; i++) {
                byte byte0 = md[i];
                buf[k++] = hexDigits[byte0 >>> 4 & 0xf];
                buf[k++] = hexDigits[byte0 & 0xf];
            }
            return new String(buf);
        } catch (Exception e) {
            return null;
        }
    }