public boolean updateUS(US user){
		Boolean isUpdate=null;
		connectionDB();
		String sql=" update US set userName=?,sex=?,age=?,telphone=?,address=? where userId=?";
		try {
			ps=conn.prepareStatement(sql);
			ps.setString(1, user.getUserName());
			ps.setString(2, user.getSex());
			ps.setInt(3, user.getAge());
			ps.setString(4, user.getTelphone());
			ps.setString(5,user.getAddress());
			ps.setLong(6, user.getUserId());
			int rows=ps.executeUpdate();
			isUpdate=rows>0?true:false;
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}finally{
			closeDB();
		}
		return isUpdate;
	}