Contacts Projects : Delete Contact

package conpack;

import java.awt.event.ActionEvent;

import java.awt.event.ActionListener;

import java.awt.event.ItemEvent;

import java.awt.event.ItemListener;

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.PreparedStatement;

import java.sql.ResultSet;

import java.sql.Statement;

import javax.swing.DefaultListModel;

import javax.swing.JButton;

import javax.swing.JFrame;

import javax.swing.JLabel;

import javax.swing.JList;

import javax.swing.JTextField;

import javax.swing.JOptionPane;

import javax.swing.event.ListSelectionEvent;

import javax.swing.event.ListSelectionListener;

public class DeleteContact extends JFrame implements ActionListener,ListSelectionListener{

     

      JButton b,d;

      JTextField name;

      JLabel i,k;

      JList list1;

    DefaultListModel model ;

     

      DeleteContact()

      {

      setTitle("Delete Contact");

      setLayout(null);

     

      model = new DefaultListModel();

      list1 = new JList(model);

      list1.setBounds(100,70,100,100);

      add(list1);

      // Initialize the list with items

      list1.addListSelectionListener(this);

     

      b=new JButton("Delete");

      b.setBounds(20,200, 100,20);

      add(b);

      b.addActionListener(this);

     

      d=new JButton("Delete All");

      d.setBounds(180,200, 100,20);

      add(d);

      d.addActionListener(this);

     

     

      name=new JTextField(5);

      name.setBounds(100, 20, 100, 20);

      add(name);

     

     

      try{

             

            Class.forName("oracle.jdbc.driver.OracleDriver");

            Connection con=

DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:XE", "system","system");

           

           

            Statement st=con.createStatement();

            String str = name.getText();

           

            ResultSet rs=st.executeQuery("select * from contacts");

          int i = 0;

            while(rs.next()){

            model.add(i,rs.getString("nam"));

            i++;

          

            }

           

     

        }

      catch(Exception e1)

      {

            System.out.println(e1);

      }

     

     

     

}

      public void valueChanged(ListSelectionEvent e) {

            //number.setText(list.getSelectedValue().toString());

             try{

                    

                        Class.forName("oracle.jdbc.driver.OracleDriver");

                        Connection con=

DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:XE", "system","system");

                       

                       

                        Statement st=con.createStatement();

                        String str = list1.getSelectedValue().toString();

ResultSet rs=st.executeQuery("select num from contacts where nam = '"+str+"'");

                       

                     

                        while(rs.next()){

                 

                              name.setText(rs.getString(1));

            

                        }

                       

                 

                    }

                  catch(Exception e1)

                  {

                        System.out.println(e1);

                       

                  }

           

      }

           

            @Override

            public void actionPerformed(ActionEvent e) {

                  if(e.getSource()== b) // delete one by one

                   {

                  try{

                       

if((JOptionPane.showConfirmDialog(this, "Do you Want to delete?"))==0)

                        {

                       

                        Class.forName("oracle.jdbc.driver.OracleDriver");

                        Connection con=

DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:XE", "system","system");

                       

PreparedStatement pr=con.prepareStatement("delete from contacts where nam=(?)");

     

                        pr.setString(1,list1.getSelectedValue().toString());

                                   

                       

                        pr.executeUpdate();

                       

                        JOptionPane.showMessageDialog(this, "contact deleted");

                         dispose();

                         windows me = new windows();

                     me.setVisible(true);

                     me.setLocation(500, 400);

                       

                        }

                        else

                              {

JOptionPane.showMessageDialog(this, "operation failed");dispose();

                             

                               dispose();

                               windows me = new windows();

                           me.setVisible(true);

                           me.setLocation(500, 400);

                              }

                  }

                  catch(Exception e1)

                  {

                        System.out.println(e1);dispose();

                         dispose();

                         windows me = new windows();

                     me.setVisible(true);

                     me.setLocation(500, 400);

                  }

           

                   }

                 

                  if(e.getSource()== d) // delete all

                   {

                  try{

                 

if((JOptionPane.showConfirmDialog(this, "Do you Want to delete All?"))==0)

                        {

                       

                        Class.forName("oracle.jdbc.driver.OracleDriver");

                        Connection con=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:XE", "system","system");

                       

PreparedStatement pr = con.prepareStatement("TRUNCATE TABLE contacts");

     

                 

                       

                         pr.executeUpdate();

                       

JOptionPane.showMessageDialog(this, "All contacts deleted");

                         dispose();

                         windows me = new windows();

                     me.setVisible(true);

                     me.setLocation(500, 400);

                       

                        }

                        else

                              {

JOptionPane.showMessageDialog(this, "operation failed");dispose();

                             

                               dispose();

                               windows me = new windows();

                           me.setVisible(true);

                           me.setLocation(500, 400);

                              }

                  }

                  catch(Exception e1)

                  {

                       

                         System.out.println(e1);dispose();

                         dispose();

                         windows me = new windows();

                     me.setVisible(true);

                     me.setLocation(500, 400);

                    

                  }

           

                   }

           

            }

            public static void main(String ar[])

            {

                  DeleteContact as=new DeleteContact();

                  as.setSize(300, 300);

                  as.setVisible(true);

                  as.setLocation(500, 400);

            }

}