if(stxxmskhk.getXxs() != null){
StringBuffer xxs = new StringBuffer();
xxs.append("update stxxmskhk set xxs=? where stdm =?");
psupdate = conn.prepareStatement(xxs.toString());
psupdate.setCharacterStream(1, new StringReader(stxxmskhk.getXxs()),stxxmskhk.getXxs().length());