如何从DB和JTable中删除选定的行？

in this code it just delete row from JTable and i want to delete from DB and when run this it delete from JTable and apper error : java.lang.ArrayIndexOutOfBoundsException: 2 >= 2 but not delete from DB how to solve this ?

在这段代码中,它只是从JTable中删除行,我想从DB中删除,并且在运行时从JTable和apper错误中删除:java.lang.ArrayIndexOutOfBoundsException:2> = 2但是没有从DB中删除如何解决这个问题?

    private final JPanel panel_09 = new JPanel();
    JScrollPane scrollPane_09 = new JScrollPane();
    final DefaultTableModel TableModel09 = new DefaultTableModel(new String[]{"Picture", "Item", "Price", "After Discount"}, 0);
    final JTable table_09 = new JTable(TableModel09);
    JButton btnNewButton_09 = new JButton("Delete Item");

    btnNewButton_09.addActionListener ( new ActionListener() {


    public void actionPerformed(ActionEvent arg0) {
        try {
            int selectedPlanet = table_09.getSelectedRow();
            TableModel09.removeRow((int) selectedPlanet);
            Object desc = table_09.getModel().getValueAt(selectedPlanet, 4);
            Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/login", "root", "123");
            String query = "delete from flyer_item where discount=desc";
            java.sql.PreparedStatement ps = conn.prepareStatement(query);
            ps.setString(1, (String) desc);
            ps.executeUpdate();

        } catch (Exception ex) {
            System.err.println(ex);
        }

    }
}
);

1 个解决方案

#1

You removed your Object from your model before you get the desc :

在获得desc之前,您已从模型中删除了Object:

int selectedPlanet = table_09.getSelectedRow();//<<--this will equal 2

TableModel09.removeRow((int) selectedPlanet);//<<----remove 2

So now

Object desc = table_09.getModel().getValueAt(selectedPlanet, 4);
//when you try to `getValueAt(2,4)` you get this error 
//"java.lang.ArrayIndexOutOfBoundsException: 2 >= 2"

To avoid this problem, you have tp get your Object before you remove the row :

要避免此问题,请在删除行之前获取对象:

int selectedPlanet = table_09.getSelectedRow();
Object desc = table_09.getModel().getValueAt(selectedPlanet, 4);
TableModel09.removeRow((int) selectedPlanet);

Then, you will get another error of SQL, because to set Parameters to PreparedStatement you have to use ? :

然后,您将得到另一个SQL错误,因为要将参数设置为PreparedStatement,您必须使用? :

String query="delete from flyer_item where discount = ?";
//----------------------------------------------------^
java.sql.PreparedStatement ps = conn.prepareStatement(query);
ps.setString(1,(String) desc);

#1