void piccerbtn_actionPerformed(ActionEvent e) {
    jLabel2.setText("");
    Object obj;
    Image imageobj;
    try { // 執行SQL指令
      sqlcom = "SELECT * FROM Picture,User WHERE Picture.Machine=User.Machine AND User.Machine='"+machNum+"'";
      System.out.println(sqlcom);
      rs = jdbc.stmt.executeQuery(sqlcom);
      while (rs.next()) { // 使用迴圈取得記錄資料
        obj = rs.getObject("Pic");
        imageobj = (Image) obj;
        //System.out.println(obj);
        //jLabel2.setText(obj);
        //jLabel2.setIcon(imageobj);
      }
    }
    catch (SQLException ex) {
      System.out.println(ex.getMessage());
    }
  }