public BasicInf getBasicInf(String staId){
          BasicInf BasicInf=null;
          try{
              ps = connection.prepareStatement("select * from BasicInf where staId=?");
              ps.setString(1,staId);
              ResultSet rs = ps.executeQuery();
              while (rs.next()) {
                  System.out.println(rs.getString(1));
                  System.out.println(rs.getString(2));
                  System.out.println(rs.getString(3));
                  System.out.println(rs.getString(4));
                  
                  BasicInf.setStaId(rs.getString(1));
                  BasicInf.setBirthday(rs.getString(2));
                  BasicInf.setNation(rs.getString(4));
                  BasicInf.setSex(rs.getString(3));
                  return BasicInf;
              }
          }catch(Exception e)
          {
              e.printStackTrace();
          }
          return BasicInf;
      }