Código:
import java.awt.*;
import java.awt.event.*;
import java.sql.*;
class frmeliminarcategAbout extends Dialog implements WindowListener,ActionListener
{ private Button btok, btok1;
public Label lblcap;
private Panel p,p2,p3;
public frmeliminarcategAbout(Frame f)
{
super(f,"Eliminar registro",true);
btok=new Button("Si");
btok1=new Button("No");
p=new Panel();
p2=new Panel();
p3=new Panel();
lblcap=new Label("Esta seguro de eliminar??");
p.add(lblcap);
p2.add(btok);
p3.add(btok1);
add("Center",p);
add("East",p2);
add("West",p3);
addWindowListener(this);
btok.addActionListener(this);
btok1.addActionListener(this);
setTitle("Eliminar registro");
setSize(110,150);
Rectangle r = f.getBounds();
setBounds((int)(r.getX()+r.getWidth()/2-125),(int)(r.getY()+r.getHeight()/2-50),250,80);
setBackground(new Color(255,255,255));
}
public void windowOpened(WindowEvent e) {}
public void windowClosing(WindowEvent e) { dispose();}
public void windowClosed(WindowEvent e) {}
public void windowIconified(WindowEvent e){}
public void windowDeiconified(WindowEvent e){}
public void windowActivated(WindowEvent e){}
public void windowDeactivated(WindowEvent e){}
public void actionPerformed(ActionEvent e)
{
if(e.getSource()==btok1)
{
dispose();
}
else if(e.getSource()==btok){
String sql;
// sql="delete from categoria_art where id_categ ='" + txtid.getText()+"'";
sql="delete from categoria_art where id_categ = 1";
dispose();
}
}
}
class frmeliminarcategMessageBox extends Dialog implements WindowListener,ActionListener
{
private Button btok;
public Label lblcap;
private Panel p,p2;
public frmeliminarcategMessageBox(Frame f)
{
super(f,"Control de Almacen",true);
btok=new Button("Aceptar");
p=new Panel();
p2=new Panel();
lblcap=new Label("");
p.add(lblcap);
p2.add(btok);
add("Center",p);
add("South",p2);
addWindowListener(this);
btok.addActionListener(this);
setTitle("A cerca de");
Rectangle r = f.getBounds();
setBounds((int)(r.getX()+r.getWidth()/2-125),(int)(r.getY()+r.getHeight()/2-50),250,100);
setBackground(Color.gray);
}
public static void Show(String msg,String title,Frame parent)
{
frmeliminarcategMessageBox msgbox = new frmeliminarcategMessageBox(parent);
msgbox.lblcap.setText(msg);
msgbox.setTitle(title);
msgbox.show();
}
public void windowOpened(WindowEvent e) {}
public void windowClosing(WindowEvent e) { dispose();}
public void windowClosed(WindowEvent e) {}
public void windowIconified(WindowEvent e){}
public void windowDeiconified(WindowEvent e){}
public void windowActivated(WindowEvent e){}
public void windowDeactivated(WindowEvent e){}
public void actionPerformed(ActionEvent e) { if(e.getSource()==btok) dispose(); }
}
class frmeliminarcategConnection
{
public static Connection getConnection()
{
Connection con=null;
try
{
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
con=DriverManager.getConnection("jdbc:odbc:dnsalmacen","","");
}
catch(java.lang.Exception e)
{
System.out.println(e);
}
return con;
}
public static ResultSet executeQuery(String stSQL) throws Exception
{
Connection cn = getConnection();
Statement st = cn.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,ResultSet.CONCUR_READ_ONLY);
ResultSet rs = st.executeQuery(stSQL);
return rs;
}
public static int executeUpdate(String stSQL) throws Exception
{
Connection cn = getConnection();
Statement st = cn.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,ResultSet.CONCUR_READ_ONLY);
int n = st.executeUpdate(stSQL);
return n;
}
}
////////////////////////INICIO DEL FORMULARIO//////////////////
public class frmeliminarcateg extends Frame implements WindowListener,ActionListener
{
TextField txtid,txtname,txtage;
String lbls[] = { "Código","Nombre","Descripción"};
Button btMove[] = { new Button("<<"),new Button("<"),
new Button(">"),new Button(">>")
};
Button btActions[] = { new Button("Eliminar")
};
String stcurId;
boolean flag;
public Connection conn;
public Statement stmt,s1;
public ResultSet rs,r1;
public frmeliminarcateg()
{ setLayout(null);
flag=false;
for(int i=0;i<lbls.length;i++)
{
Label lbl=new Label(lbls[i]);
lbl.setBounds(20,60+i*30,100,20);
add(lbl);
}
for(int i=0;i<btMove.length;i++)
{
btMove[i].setBounds(20+i*50,220,50,20);
add(btMove[i]);
btMove[i].addActionListener(this);
}
for(int i=0;i<btActions.length;i++)
{
btActions[i].setBounds(270,60+i*25,60,20);
add(btActions[i]);
btActions[i].addActionListener(this);
}
add(txtid=new TextField(10));
add(txtname=new TextField(30));
add(txtage=new TextField(50));
txtid.setBounds(130,60,60,20);
txtname.setBounds(130,90,120,20);
txtage.setBounds(130,120,120,50);
addWindowListener(this);
setSize(360,250);
connect();
EnableFields(false);
setBackground(Color.lightGray);
}
private void EnableFields(boolean b)
{
txtid.setEnabled(b);
txtname.setEnabled(b);
txtage.setEnabled(b);
btMove[0].setEnabled(!b);
btMove[1].setEnabled(!b);
btMove[2].setEnabled(!b);
btMove[3].setEnabled(!b);
btActions[0].setEnabled(!b);
}
public void windowOpened(WindowEvent e) {}
public void windowClosing(WindowEvent e) { System.exit(0);}
public void windowClosed(WindowEvent e) {}
public void windowIconified(WindowEvent e){}
public void windowDeiconified(WindowEvent e){}
public void windowActivated(WindowEvent e){}
public void windowDeactivated(WindowEvent e){}
public void connect()
{
try
{
rs=frmeliminarcategConnection.executeQuery("select * from categoria_art");
if(rs.next()) Display(rs);
}
catch(SQLException e)
{
System.out.println(e);
}
catch(java.lang.Exception ex)
{
ex.printStackTrace();
System.out.println(ex);
}
}
public void actionPerformed(ActionEvent e)
{
String stAction = e.getActionCommand();
if(stAction.equals("Si"))
{
// int valor = txtid.getText();
String sql;
sql="delete from categoria_art where id_categ ='" + txtid.getText()+"'";
try
{
stmt.executeUpdate(sql);
// sql=frmeliminarcategConnection.executeUpdate("delete from tblStud where StudID ='"+txtid.getText()+"'");
sql="delete from categoria_art where id_categ ='" + txtid.getText()+"'";
}
catch(SQLException e1) {}
}
else if(stAction.equals("Eliminar"))
{
// String sql;
// sql="delete from categoria_art where id_categ =" + txtid.getText();
frmeliminarcategAbout a = new frmeliminarcategAbout(this);
a.show();
/* try
{
stmt.executeUpdate(sql);
// sql=frmeliminarcategConnection.executeUpdate("delete from tblStud where StudID ='"+txtid.getText()+"'");
sql="delete from categoria_art where id_categ =" + txtid.getText();
}
catch(SQLException e1) {}*/
}
else
{
try
{
if(e.getSource()==btMove[0])
{
if(rs.first())
{
Display(rs);
}
}
else if(e.getSource()==btMove[3])
{
if(rs.last())
{
Display(rs);
}
}
else if(e.getSource()==btMove[2])
{
if(rs.isLast())
{
rs.afterLast();
frmeliminarcategMessageBox.Show("Último Registro","Control de Almacen",this);
}
if(rs.next())
{
Display(rs);
}
}
else if(e.getSource()==btMove[1])
{
if(rs.isFirst())
{ rs.beforeFirst();
frmeliminarcategMessageBox.Show("Primer Registro","Control de Almacen",this);
}
if(rs.previous())
{
Display(rs);
}
}
}
catch(SQLException e1)
{
}
}
}
private void Display(ResultSet rs) throws SQLException
{
stcurId = rs.getString(1);
txtname.setText(rs.getString(2));
txtid.setText(stcurId);
txtage.setText(rs.getString(3));
txtid.requestFocus();
}
public String loadName(String n)
{
String name="";
try
{
ResultSet rs1= frmeliminarcategConnection.executeQuery("select nombre from categoria_art where id_categ="+n);
if(rs1.next())
name=rs1.getString("nombre");
else
name="no such id";
}
catch(Exception e2) {}
return(name);
}
public static void main(String s1[])
{
frmeliminarcateg s=new frmeliminarcateg();
s.setTitle("Formulario Mentenimiento de categoría");
s.show();
}
}
La instrucción sql 
