public static String md5(String content) { if (StringUtils.isBlank(content)) { return null; } try { byte[] b = content.getBytes("UTF-8"); MessageDigest md = MessageDigest.getInstance("MD5"); md.reset(); md.update(b); byte[] hash = md.digest(); StringBuffer outStrBuf = new StringBuffer(32); for (int i = 0; i < hash.length; i++) { int v = hash[i] & 0xFF; if (v < 16) { outStrBuf.append('0'); } outStrBuf.append(Integer.toString(v, 16).toLowerCase()); } return outStrBuf.toString(); } catch (Exception e) { MAINLOG.error("sign_utils签名错误",e); } return null; }