我正在写一个简单的MySQL编辑器。我的问题是，在我从组合框中选择数据库中的一个新表并加载它，然后选择一行并尝试删除它后，getSelectedRow()返回 -1 并生成一个异常，但是当我从中删除一行时不会发生这种情况在我的程序开始时加载的表。
这是来自 2 个文件的关键代码部分（在同一代码引用中）：
package omnisql;
import java.sql.*;
import java.util.*;
public class getData
{
static Connect c = new Connect();
static GUI g = new GUI();
static ResultSet result;
public static Vector<Vector<String>> data = new Vector<Vector<String>>();
public static String table="pracownicy";
public static Vector <String> d;
public static List <String> id;
void getData() throws SQLException
{
result=c.stmt.executeQuery("select * from "+table);
id = new ArrayList<String>();
while(result.next())
{
d=new Vector<String>();
id.add(result.getString("id"));
d.add(result.getString("id"));
d.add(result.getString("Nazwisko"));
d.add(result.getString("Imię"));
d.add(result.getString("Płeć"));
d.add(result.getString("Ulica"));
d.add(result.getString("Miejscowość"));
d.add(result.getString("Kod_pocztowy"));
d.add(result.getString("Województwo"));
d.add(result.getString("Telefon"));
data.add(d);
}
}
}
package omnisql;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.*;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import javax.swing.*;
import javax.swing.table.*;
import java.util.*;
import javax.swing.event.*;
public class GUI extends JFrame implements ActionListener, TableModelListener
{
static Connect c = new Connect();
static getData gd = new getData();
JPanel panel = new JPanel(new FlowLayout(FlowLayout.LEFT,10,5));
JPanel panel1 = new JPanel(new FlowLayout(FlowLayout.LEFT,10,5));
JPanel panel2 = new JPanel(new FlowLayout(FlowLayout.CENTER,10,5));
JPanel panel3 = new JPanel(new FlowLayout(FlowLayout.LEFT,10,5));
JLabel typbazy = new JLabel("Typ bazy: ");
JLabel wybtab = new JLabel("Wybierz tabelę: ");
JRadioButton postgre = new JRadioButton("PostgreSQL");
JRadioButton mysql = new JRadioButton("MySQL");
JRadioButton sqlite = new JRadioButton("SQLite");
ButtonGroup grupa = new ButtonGroup();
public static JComboBox tabela = new JComboBox();
JButton addrec = new JButton("Dodaj rekord");
JButton delrec = new JButton("Usuń rekord");
JButton reftab = new JButton("Odśwież tabelę");
JTable table;
public static DefaultTableModel model;
TableColumn column;
Vector<String> headers = new Vector<String>();
JScrollPane scroll;
static int rownumber,addrow,delrow,updaterow;
PreparedStatement pst;
String value="";
public static int height,i,firstrow=0, klick=1;
public GUI()
{
panel.add(typbazy);
grupa.add(postgre);
panel.add(postgre);
postgre.addActionListener(this);
grupa.add(mysql);
panel.add(mysql);
mysql.setSelected(rootPaneCheckingEnabled);
mysql.addActionListener(this);
grupa.add(sqlite);
panel.add(sqlite);
sqlite.addActionListener(this);
panel1.add(wybtab);
panel1.add(tabela);
tabela.setPreferredSize(new Dimension(120,20));
tabela.setBackground(Color.white);
tabela.removeAllItems();
tabela.addItem(" ");
tabela.addItem("Pracownicy");
tabela.addItem("Pracownicy 2");
tabela.setSelectedIndex(0);
tabela.addActionListener(this);
headers.add("ID");
headers.add("Nazwisko");
headers.add("Imię");
headers.add("Płeć");
headers.add("Ulica");
headers.add("Miejscowość");
headers.add("Kod_pocztowy");
headers.add("Województwo");
headers.add("Telefon");
model = new DefaultTableModel(gd.data, headers);
table = new JTable(model);
table.setRowSelectionAllowed(true);
table.getModel().addTableModelListener(this);
table.setPreferredScrollableViewportSize(new Dimension(740,159));
column = table.getColumnModel().getColumn(0);
column.setPreferredWidth(20);
column = table.getColumnModel().getColumn(1);
column.setPreferredWidth(100);
column = table.getColumnModel().getColumn(2);
column.setPreferredWidth(70);
column = table.getColumnModel().getColumn(3);
column.setPreferredWidth(70);
column = table.getColumnModel().getColumn(4);
column.setPreferredWidth(100);
column = table.getColumnModel().getColumn(5);
column.setPreferredWidth(100);
column = table.getColumnModel().getColumn(6);
column.setPreferredWidth(100);
column = table.getColumnModel().getColumn(7);
column.setPreferredWidth(100);
column = table.getColumnModel().getColumn(8);
column.setPreferredWidth(80);
scroll = new JScrollPane(table);
panel2.add(scroll);
panel3.add(addrec);
addrec.addActionListener(this);
panel3.add(delrec);
delrec.addActionListener(this);
panel3.add(reftab);
reftab.addActionListener(this);
getContentPane().setLayout(new BoxLayout(getContentPane(), BoxLayout.Y_AXIS));
getContentPane().add(panel);
getContentPane().add(panel1);
getContentPane().add(panel2);
getContentPane().add(panel3);
}
void initGUI()
{
setSize(800,340);
setTitle("OmniSQL 1.0");
setResizable(false);
setVisible(true);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
public void tableChanged(TableModelEvent e)
{
rownumber = table.getSelectedRow();
if (rownumber==-1) rownumber=0;
updaterow = Integer.parseInt(gd.id.get(rownumber));
switch (e.getType())
{
case TableModelEvent.UPDATE:
table.getRowCount();
value=table.getValueAt(table.getSelectedRow(),table.getSelectedColumn()).toString();
try
{
pst = c.con.prepareStatement("UPDATE "+gd.table+" SET "+table.getColumnName(table.getSelectedColumn())+" = '"+value+"' where id = "+updaterow+";");
pst.executeUpdate();
}
catch (SQLException err)
{
}
break;
}
}
public void actionPerformed(ActionEvent e)
{
/*if (e.getActionCommand().equals("MySQL"))
{
try
{
c.con.close();
c.connect("jdbc:mysql://localhost:3306/omnisql","root","sqlek","com.mysql.jdbc.Driver");
}
catch (ClassNotFoundException er)
{
}
catch(SQLException err)
{
}
}*/
if (tabela.getSelectedItem()=="Pracownicy")
{
gd.table="pracownicy";
try
{
model.setRowCount(0);
table.removeAll();
gd.getData();
}
catch (SQLException er)
{
}
}
if (tabela.getSelectedItem()=="Pracownicy 2")
{
gd.table="pracownicy2";
try
{
model.setRowCount(0);
gd.getData();
table.revalidate();
}
catch (SQLException er)
{
}
}
/*if(postgre.isSelected())
{
tabela.removeAllItems();
tabela.addItem("Adresy");
tabela.addItem("Adresy 2");
tabela.setSelectedIndex(0);
}
*/
/*if(mysql.isSelected())
{
tabela.removeAllItems();
tabela.addItem(" ");
tabela.addItem("Pracownicy");
tabela.addItem("Pracownicy 2");
}*/
/*
if(sqlite.isSelected())
{
tabela.removeAllItems();
tabela.addItem("Zakłady");
tabela.addItem("Zakłady 2");
tabela.setSelectedIndex(0);
}*/
if (e.getActionCommand().equals("Dodaj rekord"))
{
model.setRowCount(gd.id.size());
rownumber = model.getRowCount()-1;
if(rownumber==-1 && gd.id.size()==0)
{
rownumber=0;
gd.id.add(0, "1");
addrow=Integer.parseInt(gd.id.get(rownumber));
}
else
{
addrow=Integer.parseInt(gd.id.get(rownumber));
addrow++;
}
try
{
pst = c.con.prepareStatement("INSERT INTO "+gd.table+" (id) VALUES("+addrow+")");
pst.executeUpdate();
model.setRowCount(0);
gd.getData();
height = (int)table.getPreferredSize().getHeight();
table.scrollRectToVisible(new Rectangle(0,height,10,10));
}
catch (SQLException exc)
{
}
}
rownumber=table.getSelectedRow();
if (e.getActionCommand().equals("Usuń rekord"))
{
try
{
model.setRowCount(gd.id.size());
System.out.println(rownumber);
delrow = Integer.parseInt(gd.id.get(rownumber));
pst = c.con.prepareStatement("DELETE from "+gd.table+" where id="+delrow);
pst.executeUpdate();
model.setRowCount(0);
gd.getData();
}
catch (SQLException exc)
{
}
}
if (e.getActionCommand().equals("Odśwież tabelę"))
{
try
{
model.setRowCount(0);
gd.getData();
}
catch (SQLException exc)
{
}
}
}
}
对于这个问题的任何帮助，我将不胜感激。