public DatePicker selecteDOP;
public Label label;

String dop = ((TextField)selecteDOP.getEditor()).getText();
String msg1 ="";

@FXML
public void purchases(ActionEvent event){
    msg1 = "First name   Last name   Username   Description  Code  Size  Cost  Quantity  Date of purchase\n";
    try{
        String qr = "SELECT j_fname,j_lname,username,description,code,size,cost,quantity,dop FROM jeff INNER JOIN purchase ON jeff.j_mail = purchase.username where dop='"+dop+"'";
        rs = st.executeQuery(qr);

        while (rs.next()){
            msg1 += rs.getString("j_fname")+"  "+rs.getString("j_lname")+"  "+rs.getString("username")+"   "+rs.getString("description")+"    "+rs.getString("code")+"  "+rs.getString("size")+"  "+rs.getString("cost")+"  "+rs.getString("quantity")+"   "+rs.getString("dop")+"\n";
        }
        label.setText(msg1);

    }catch (Exception e){
        System.out.println(e);
    }

}

我试图从数据库中检索用户从datepicker中选择的特定日期的数据，但我的代码不起作用。您能建议我如何克服它吗