public String EncodeByMD5(String str) throws NoSuchAlgorithmException, UnsupportedEncodingException {
//确定一个计算方法
MessageDigest md5=MessageDigest.getInstance("MD5");
BASE64Encoder base64en=new BASE64Encoder();
//加密字符串
String newstr=base64en.encode(md5.digest(str.getBytes("utf-8")));
return newstr;
}