/*
      Chapter 9:     PhoneBook
      Programmer:    Brad Shedd
      Date:          September 09, 2006
      Filename:      PhoneBook.java
      Purpose:       This program maintains entries for a phone  book.
 */

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.util.*;

public class PhoneBook extends JFrame implements ActionListener
{  private JTextField jtfName, jtfPhone;
   private JButton jbtAdd, jbtDelete, jbtUpdate, jbtFind;
   private ArrayList nameList, phoneList;

    public static void main(String[] args)
    {
      int width = 200;
      int height = 130;
        PhoneBook frame = new PhoneBook();
        frame.pack();
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
      frame.setSize(width, height);
      frame.centerOnScreen(width, height);
      frame.setVisible(true);
    }

    public PhoneBook()
    {
        nameList = new ArrayList(20); //sets up for 20 entries
        phoneList = new ArrayList(20); //sets up for 20 entries

        setTitle("Phone Book");

        JPanel p = new JPanel();
        p.setLayout(new FlowLayout());
        p.add(new JLabel("Name:   "));
       p.add(jtfName = new JTextField(20));
       p.add(new JLabel("Phone:   "));
       p.add(jtfPhone = new JTextField(20));

       p.add(jbtAdd = new JButton("Add"));
        p.add(jbtDelete = new JButton("Delete"));
        p.add(jbtUpdate = new JButton("Update"));
        p.add(jbtFind = new JButton("Find"));

        jbtAdd.addActionListener(this);
        jbtDelete.addActionListener(this);
        jbtUpdate.addActionListener(this);
        jbtFind.addActionListener(this);

        getContentPane().setLayout(new BorderLayout(10,10));
        getContentPane().add(p,BorderLayout.CENTER);

        addWindowListener(new WindowAdapter() {
         public void windowClosing(WindowEvent e) { System.exit(0); }
        });
    }

   public void centerOnScreen(int width, int height)
   {
     int top, left, x, y;

     // Get the screen dimension
     Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();

     // Determine the location for the top left corner of the frame
     x = (screenSize.width - width)/2;
     y = (screenSize.height - height)/2;
     top = (x < 0) ? 0 : x;
     left = (y < 0) ? 0 : y;

     // Set the frame to the specified location
     this.setLocation(top, left);
   }

   public void actionPerformed(ActionEvent e)
    {
      String nameEntered, phoneEntered;
      int index;

      nameEntered = jtfName.getText();
      phoneEntered= jtfPhone.getText();

      if(nameEntered.length() > 0)
      {
         if(e.getSource() == jbtAdd)      // user clicked Add
            {
               if(phoneEntered.length() > 0)
               {
                  try
                  {
                     addEntry(nameEntered, phoneEntered);
                     JOptionPane.showMessageDialog(this,"Entry added to phone book.", "Successful!", JOptionPane.INFORMATION_MESSAGE);

                        jtfName.setText("");
                        jtfPhone.setText("");
                        jtfName.requestFocus();
               }
                  catch (Exception ex)
               {
                         JOptionPane.showMessageDialog(this, ex.getMessage(), "Add failed.", JOptionPane.ERROR_MESSAGE);

               }
            }
            else
               {
               JOptionPane.showMessageDialog(this,"Please enter a phone number.", "Invalid entry.Try again.", JOptionPane.INFORMATION_MESSAGE);
               jtfPhone.requestFocus();
            }
          }

            else if  (e.getSource() == jbtUpdate)     // user clicked Update
            {
               try
                  {
                     updateEntry(nameEntered, phoneEntered);
                     JOptionPane.showMessageDialog(this,"Entry updated in phone book.", "Successful!", JOptionPane.INFORMATION_MESSAGE);

                           jtfName.setText("");
                        jtfPhone.setText("");
                        jtfName.requestFocus();
               }
               catch (Exception ex)
            {
                      JOptionPane.showMessageDialog(this, ex.getMessage(), "Update failed.", JOptionPane.ERROR_MESSAGE);

            }
         }

            else if  (e.getSource() == jbtDelete)     // user clicked Delete
            {
               try
               {
                  deleteEntry(nameEntered);
                  JOptionPane.showMessageDialog(this,"Entry deleted in phone book.", "Successful!", JOptionPane.INFORMATION_MESSAGE);

                     jtfName.setText("");
                  jtfPhone.setText("");
                  jtfName.requestFocus();
            }
               catch (Exception ex)
            {
                      JOptionPane.showMessageDialog(this, ex.getMessage(), "Delete failed.", JOptionPane.ERROR_MESSAGE);

                   jtfName.requestFocus();
            }
         }
         else if  (e.getSource() == jbtFind)    // user clicked Find
            {
              try
              {
               index = findEntry(nameEntered);
               jtfName.setText((String)nameList.get(index));
               jtfPhone.setText((String)phoneList.get(index));
               jtfName.requestFocus();
           }
           catch (Exception ex)
           {
                   JOptionPane.showMessageDialog(this, ex.getMessage(), "Find failed.", JOptionPane.ERROR_MESSAGE);

               jtfName.requestFocus();
           }
         }
      }
      else
      {
         JOptionPane.showMessageDialog(this,"Please enter a name.", "Invalid entry. Try again.", JOptionPane.ERROR_MESSAGE);

         jtfName.requestFocus();
      }
   }

   private void addEntry(String name, String phone) throws Exception
   {
      if(!nameList.contains(name))
      {
         name.trim();
         phone.trim();
         nameList.add(name);
         phoneList.add(phone);
      }
      else
         throw new Exception("Name already in phone book.");
   }

     private void updateEntry(String name, String phone) throws Exception
       {
               int index = 0;

            name.trim();
            phone.trim();
            index = nameList.indexOf(name);
            if (index < 0)
               throw new Exception("Name not in phone book.");
         else
         {
            nameList.set(index, name);
            phoneList.set(index, phone);
         }
      }
        private void deleteEntry(String name)throws Exception
        {
         int index = 0;
         index = nameList.indexOf(name.trim());
         if(index < 0)
            throw new Exception("Name not in phone book.");
        else
        {
         nameList.remove(index);
         phoneList.remove(index);
        }
    }
    private int findEntry(String name)throws Exception
        {
         int index = 0;
         index = nameList.indexOf(name.trim());
         if(index < 0)
            throw new Exception("Name not in phone book.");

            return index;
        }
   }

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