code: public final String getClientUUID()
      {
          if (null == m_cliuuid)
          {
              if (LocalStorage.get().isSupported())
              {
                  m_cliuuid = StringOps.toTrimOrNull(LocalStorage.get().getString(X_CLIENT_UUID_HEADER));
              }
              if (null == m_cliuuid)
              {
                  m_cliuuid = StringOps.toTrimOrNull(ClientStorage.get().getString(X_CLIENT_UUID_HEADER));
              }
              if (null == m_cliuuid)
              {
                  m_cliuuid = UUID.uuid();
  
                  if (LocalStorage.get().isSupported())
                  {
                      LocalStorage.get().putString(X_CLIENT_UUID_HEADER, m_cliuuid);
                  }
                  else
                  {
                      ClientStorage.get().putString(X_CLIENT_UUID_HEADER, m_cliuuid);
                  }
              }
              else
              {
                  final String temp = XSS.get().clean(m_cliuuid);
  
                  if (false == temp.equals(m_cliuuid))
                  {
                      m_cliuuid = temp;
  
                      if (LocalStorage.get().isSupported())
                      {
                          LocalStorage.get().putString(X_CLIENT_UUID_HEADER, m_cliuuid);
                      }
                      else
                      {
                          ClientStorage.get().putString(X_CLIENT_UUID_HEADER, m_cliuuid);
                      }
                  }
              }
          }
          return m_cliuuid;
      }
docs: /*
  This should uniquely identify the browser by UUID in ClientStorage till cache is cleared.
  There is no other way to do "user browser identification" without getting REALLY, REALLY,
  REALLY hacky!!! ( zombie cookies, Canvas Finger printing, etc. ), which are all nefarious
  and now well recieved, for good reason.
  
  Extra checks to rule out LocalStorage cache poisoning ( OK Laugh, I have seen it happen )
  
  DSJ