public String getAvatarHash() {
byte[] data = getAvatar();
if (data == null) return null;
MessageDigest digest;
try {
digest = MessageDigest.getInstance("SHA-1");
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
return null;
}
digest.update(data);
return StringUtils.encodeHex(digest.digest());
}
