Error-NullPointer

This is the error that I am getting when I run my program.  Can you tell me what the problem is for this program?

Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
      at AddressBookDisplay$9.windowClosing(AddressBookDisplay.java:267)
      at java.awt.AWTEventMulticaster.windowClosing(AWTEventMulticaster.java:332)
      at java.awt.Window.processWindowEvent(Window.java:1865)
      at javax.swing.JFrame.processWindowEvent(JFrame.java:274)
      at java.awt.Window.processEvent(Window.java:1823)
      at java.awt.Component.dispatchEventImpl(Component.java:4651)
      at java.awt.Container.dispatchEventImpl(Container.java:2099)
      at java.awt.Window.dispatchEventImpl(Window.java:2478)
      at java.awt.Component.dispatchEvent(Component.java:4481)
      at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:643)
      at java.awt.EventQueue.access$000(EventQueue.java:84)
      at java.awt.EventQueue$1.run(EventQueue.java:602)
      at java.awt.EventQueue$1.run(EventQueue.java:600)
      at java.security.AccessController.doPrivileged(Native Method)
      at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:87)
      at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:98)
      at java.awt.EventQueue$2.run(EventQueue.java:616)
      at java.awt.EventQueue$2.run(EventQueue.java:614)
      at java.security.AccessController.doPrivileged(Native Method)
      at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:87)
      at java.awt.EventQueue.dispatchEvent(EventQueue.java:613)
      at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)
      at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
      at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)
      at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
      at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
      at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.awt.FlowLayout;
import java.awt.GridLayout;
import java.util.List;
import javax.swing.JButton;
import javax.swing.Box;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.WindowConstants;
import javax.swing.BoxLayout;
import javax.swing.BorderFactory;
import javax.swing.JOptionPane;

public class AddressBookDisplay extends JFrame
{
   private Person currentEntry;
   private PersonQueries personQueries;
   private List< Person > results;  
   private int numberOfEntries = 0;
   private int currentEntryIndex;

   private JButton browseButton;
   private JLabel emailLabel;
   private JTextField emailTextField;
   private JLabel firstNameLabel;
   private JTextField firstNameTextField;
   private JLabel idLabel;
   private JTextField idTextField;
   private JTextField indexTextField;
   private JLabel lastNameLabel;
   private JTextField lastNameTextField;
   private JTextField maxTextField;
   private JButton nextButton;
   private JLabel ofLabel;
   private JLabel phoneLabel;
   private JTextField phoneTextField;
   private JButton previousButton;
   private JButton queryButton;
   private JLabel queryLabel;
   private JPanel queryPanel;
   private JPanel navigatePanel;
   private JPanel displayPanel;
   private JTextField queryTextField;
   private JButton insertButton;
   private JButton updateButton;
   private JButton deleteButton;
      
   // no-argument constructor
   public AddressBookDisplay()
   {
      super( "Address Book" );
     
      // establish database connection and set up PreparedStatements
     // personQueries = new PersonQueries();
     
      // create GUI
      navigatePanel = new JPanel();
      previousButton = new JButton();
      indexTextField = new JTextField( 2 );
      ofLabel = new JLabel();
      maxTextField = new JTextField( 2 );
      nextButton = new JButton();
      displayPanel = new JPanel();
      idLabel = new JLabel();
      idTextField = new JTextField( 10 );
      firstNameLabel = new JLabel();
      firstNameTextField = new JTextField( 10 );
      lastNameLabel = new JLabel();
      lastNameTextField = new JTextField( 10 );
      emailLabel = new JLabel();
      emailTextField = new JTextField( 10 );
      phoneLabel = new JLabel();
      phoneTextField = new JTextField( 10 );
      queryPanel = new JPanel();
      queryLabel = new JLabel();
      queryTextField = new JTextField( 10 );
      queryButton = new JButton();
      browseButton = new JButton();
      insertButton = new JButton();
      updateButton = new JButton();
            deleteButton = new JButton();

           setLayout( new FlowLayout( FlowLayout.CENTER, 10, 10 ) );
      setSize( 400, 400 );
      setResizable( false );

      navigatePanel.setLayout(
         new BoxLayout( navigatePanel, BoxLayout.X_AXIS ) );

      previousButton.setText( "Previous" );
      previousButton.setEnabled( false );
      previousButton.addActionListener(
         new ActionListener()
         {
            public void actionPerformed( ActionEvent evt )
            {
               previousButtonActionPerformed( evt );
            } // end method actionPerformed
         } // end anonymous inner class
      ); // end call to addActionListener

      navigatePanel.add( previousButton );
      navigatePanel.add( Box.createHorizontalStrut( 10 ) );

      indexTextField.setHorizontalAlignment(
         JTextField.CENTER );
      indexTextField.addActionListener(
         new ActionListener()
         {
            public void actionPerformed( ActionEvent evt )
            {
               indexTextFieldActionPerformed( evt );
            } // end method actionPerformed
         } // end anonymous inner class
      ); // end call to addActionListener

      navigatePanel.add( indexTextField );
      navigatePanel.add( Box.createHorizontalStrut( 10 ) );

      ofLabel.setText( "of" );
      navigatePanel.add( ofLabel );
      navigatePanel.add( Box.createHorizontalStrut( 10 ) );

      maxTextField.setHorizontalAlignment(
         JTextField.CENTER );
      maxTextField.setEditable( false );
      navigatePanel.add( maxTextField );
      navigatePanel.add( Box.createHorizontalStrut( 10 ) );

      nextButton.setText( "Next" );
      nextButton.setEnabled( false );
      nextButton.addActionListener(
         new ActionListener()
         {
            public void actionPerformed( ActionEvent evt )
            {
               nextButtonActionPerformed( evt );
            } // end method actionPerformed
         } // end anonymous inner class
      ); // end call to addActionListener

      navigatePanel.add( nextButton );
      add( navigatePanel );

      displayPanel.setLayout( new GridLayout( 5, 2, 4, 4 ) );

      idLabel.setText( "Address ID:" );
      displayPanel.add( idLabel );

      idTextField.setEditable( false );
      displayPanel.add( idTextField );

      firstNameLabel.setText( "First Name:" );
      displayPanel.add( firstNameLabel );
      displayPanel.add( firstNameTextField );

      lastNameLabel.setText( "Last Name:" );
      displayPanel.add( lastNameLabel );
      displayPanel.add( lastNameTextField );

      emailLabel.setText( "Email:" );
      displayPanel.add( emailLabel );
      displayPanel.add( emailTextField );

      phoneLabel.setText( "Phone Number:" );
      displayPanel.add( phoneLabel );
      displayPanel.add( phoneTextField );
      add( displayPanel );

      queryPanel.setLayout(
         new BoxLayout( queryPanel, BoxLayout.X_AXIS) );

      queryPanel.setBorder( BorderFactory.createTitledBorder(
         "Find an entry by last name" ) );
      queryLabel.setText( "Last Name:" );
      queryPanel.add( Box.createHorizontalStrut( 5 ) );
      queryPanel.add( queryLabel );
      queryPanel.add( Box.createHorizontalStrut( 10 ) );
      queryPanel.add( queryTextField );
      queryPanel.add( Box.createHorizontalStrut( 10 ) );

      queryButton.setText( "Find" );
      queryButton.addActionListener(
         new ActionListener()
         {
            public void actionPerformed( ActionEvent evt )
            {
               queryButtonActionPerformed( evt );
            } // end method actionPerformed
         } // end anonymous inner class
      ); // end call to addActionListener

      queryPanel.add( queryButton );
      queryPanel.add( Box.createHorizontalStrut( 5 ) );
      add( queryPanel );

      browseButton.setText( "Browse All Entries" );
      browseButton.addActionListener(
         new ActionListener()
         {
            public void actionPerformed( ActionEvent evt )
            {
               browseButtonActionPerformed( evt );
            } // end method actionPerformed
         } // end anonymous inner class
      ); // end call to addActionListener

      add( browseButton );

      insertButton.setText( "Insert New Entry" );
      insertButton.addActionListener(
         new ActionListener()
         {
            public void actionPerformed( ActionEvent evt )
            {
               insertButtonActionPerformed( evt );
            } // end method actionPerformed
         } // end anonymous inner class
      ); // end call to addActionListener

         add( insertButton );      
           
            updateButton.setText( "Update Current Entry" );
            updateButton.addActionListener(
                  new ActionListener()
                  {
                        public void actionPerformed( ActionEvent evt )
                        {
                              updateButtonActionPerformed( evt );
                        } // end method actionPerformed
                  } // end anonymous inner class
                  );// end call to ActionListener
           
            add( updateButton );
                        
                  deleteButton.setText( "Delete Current Entry" );
            deleteButton.addActionListener(
                  new ActionListener()
                  {
                        public void actionPerformed( ActionEvent evt )
                        {
                              deleteButtonActionPerformed( evt );
                        } // end method actionPerformed
                  } // end anonymous inner class
                  );// end call to ActionListener
           
            add( deleteButton );                        
            
      addWindowListener(
         new WindowAdapter()
         {  
            public void windowClosing( WindowEvent evt )
            {
               System.exit( 0 );
            } // end method windowClosing
         } // end anonymous inner class
      ); // end call to addWindowListener
     
      setVisible( true );
   } // end no-argument constructor

   // handles call when previousButton is clicked
   private void previousButtonActionPerformed( ActionEvent evt )
   {
      currentEntryIndex--;
     
      if ( currentEntryIndex < 0 )
         currentEntryIndex = numberOfEntries - 1;
     
            
            
            
      indexTextField.setText( "" + ( currentEntryIndex + 1 ) );
      indexTextFieldActionPerformed( evt );  
   } // end method previousButtonActionPerformed

   // handles call when nextButton is clicked
   private void nextButtonActionPerformed( ActionEvent evt )
   {
      currentEntryIndex++;
     
      if ( currentEntryIndex >= numberOfEntries )
         currentEntryIndex = 0;
     
      indexTextField.setText( "" + ( currentEntryIndex + 1 ) );
      indexTextFieldActionPerformed( evt );
   } // end method nextButtonActionPerformed

   // handles call when queryButton is clicked
   private void queryButtonActionPerformed( ActionEvent evt )
   {
      results =
         personQueries.getPeopleByLastName( queryTextField.getText() );
      numberOfEntries = results.size();
     
      if ( numberOfEntries != 0 )
      {
         currentEntryIndex = 0;
         currentEntry = results.get( currentEntryIndex );
         idTextField.setText("" + currentEntry.getAddressID() );
         firstNameTextField.setText( currentEntry.getFirstName() );
         lastNameTextField.setText( currentEntry.getLastName() );
         emailTextField.setText( currentEntry.getEmail() );
         phoneTextField.setText( currentEntry.getPhoneNumber() );
         maxTextField.setText( "" + numberOfEntries );
         indexTextField.setText( "" + ( currentEntryIndex + 1 ) );
         nextButton.setEnabled( true );
         previousButton.setEnabled( true );
      } // end if
      else
         browseButtonActionPerformed( evt );
   } // end method queryButtonActionPerformed

   // handles call when a new value is entered in indexTextField
   private void indexTextFieldActionPerformed( ActionEvent evt )
   {
      currentEntryIndex =
         ( Integer.parseInt( indexTextField.getText() ) - 1 );
     
      if ( numberOfEntries != 0 && currentEntryIndex < numberOfEntries )
      {
         currentEntry = results.get( currentEntryIndex );
         idTextField.setText("" + currentEntry.getAddressID() );
         firstNameTextField.setText( currentEntry.getFirstName() );
         lastNameTextField.setText( currentEntry.getLastName() );
         emailTextField.setText( currentEntry.getEmail() );
         phoneTextField.setText( currentEntry.getPhoneNumber() );
         maxTextField.setText( "" + numberOfEntries );
         indexTextField.setText( "" + ( currentEntryIndex + 1 ) );
      } // end if
    } // end method indexTextFieldActionPerformed

   // handles call when browseButton is clicked
   private void browseButtonActionPerformed( ActionEvent evt )
   {
      try
      {
         results = personQueries.getAllPeople();
         numberOfEntries = results.size();
     
         if ( numberOfEntries != 0 )
         {
            currentEntryIndex = 0;
            currentEntry = results.get( currentEntryIndex );
            idTextField.setText("" + currentEntry.getAddressID() );
            firstNameTextField.setText( currentEntry.getFirstName() );
            lastNameTextField.setText( currentEntry.getLastName() );
            emailTextField.setText( currentEntry.getEmail() );
            phoneTextField.setText( currentEntry.getPhoneNumber() );
            maxTextField.setText( "" + numberOfEntries );
            indexTextField.setText( "" + ( currentEntryIndex + 1 ) );
            nextButton.setEnabled( true );
            previousButton.setEnabled( true );
         } // end if
      } // end try
      catch ( Exception e )
      {
         e.printStackTrace();
      } // end catch
   } // end method browseButtonActionPerformed

   // handles call when insertButton is clicked
   private void insertButtonActionPerformed( ActionEvent evt )
   {
      int result = personQueries.addPerson( firstNameTextField.getText(),
         lastNameTextField.getText(), emailTextField.getText(),
         phoneTextField.getText() );
     
      if ( result == 1 )
         JOptionPane.showMessageDialog( this, "Person added!",
            "Person added", JOptionPane.PLAIN_MESSAGE );
      else
         JOptionPane.showMessageDialog( this, "Person not added!",
            "Error", JOptionPane.PLAIN_MESSAGE );
         
      browseButtonActionPerformed( evt );
   } // end method insertButtonActionPerformed
   
      private void updateButtonActionPerformed( ActionEvent evt )
      {
         int result = personQueries.updatePerson( firstNameTextField.getText(),
         lastNameTextField.getText(), emailTextField.getText(),
         phoneTextField.getText() );
            if ( result == 1 )
                  JOptionPane.showMessageDialog( this, "Person updated!",
                        "Person updated", JOptionPane.PLAIN_MESSAGE );
            else
                  JOptionPane.showMessageDialog( this, "Person not updated!",
                        "Person not updated", JOptionPane.PLAIN_MESSAGE );
                       
            updateButtonActionPerformed( evt );
      } // end method updateButtonActionPerformed
            
            private void   deleteButtonActionPerformed(ActionEvent evt )
      {
           int result = personQueries.deletePerson(Integer.parseInt(idTextField.getText()) );
     
      if ( result == 1 )
         JOptionPane.showMessageDialog( this, "Person Deleted!",
            "Person Data Updated!", JOptionPane.PLAIN_MESSAGE );
      else
         JOptionPane.showMessageDialog( this, "Person Data not Deleted!",
            "Error", JOptionPane.PLAIN_MESSAGE );
            browseButtonActionPerformed(evt);
      } // end method deleteButtonActionPerformed
   
      public static void main( String args[] )
   {
      new AddressBookDisplay();
   } // end method main
} //

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.awt.FlowLayout;
import java.awt.GridLayout;
import java.util.List;
import javax.swing.JButton;
import javax.swing.Box;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.WindowConstants;
import javax.swing.BoxLayout;
import javax.swing.BorderFactory;
import javax.swing.JOptionPane;

public class AddressBookDisplay extends JFrame
{
   private Person currentEntry;
   private PersonQueries personQueries;
   private List< Person > results;  
   private int numberOfEntries = 0;
   private int currentEntryIndex;

   private JButton browseButton;
   private JLabel emailLabel;
   private JTextField emailTextField;
   private JLabel firstNameLabel;
   private JTextField firstNameTextField;
   private JLabel idLabel;
   private JTextField idTextField;
   private JTextField indexTextField;
   private JLabel lastNameLabel;
   private JTextField lastNameTextField;
   private JTextField maxTextField;
   private JButton nextButton;
   private JLabel ofLabel;
   private JLabel phoneLabel;
   private JTextField phoneTextField;
   private JButton previousButton;
   private JButton queryButton;
   private JLabel queryLabel;
   private JPanel queryPanel;
   private JPanel navigatePanel;
   private JPanel displayPanel;
   private JTextField queryTextField;
   private JButton insertButton;
   private JButton updateButton;
   private JButton deleteButton;
      
   // no-argument constructor
   public AddressBookDisplay()
   {
      super( "Address Book" );
     
      // establish database connection and set up PreparedStatements
     // personQueries = new PersonQueries();
     
      // create GUI
      navigatePanel = new JPanel();
      previousButton = new JButton();
      indexTextField = new JTextField( 2 );
      ofLabel = new JLabel();
      maxTextField = new JTextField( 2 );
      nextButton = new JButton();
      displayPanel = new JPanel();
      idLabel = new JLabel();
      idTextField = new JTextField( 10 );
      firstNameLabel = new JLabel();
      firstNameTextField = new JTextField( 10 );
      lastNameLabel = new JLabel();
      lastNameTextField = new JTextField( 10 );
      emailLabel = new JLabel();
      emailTextField = new JTextField( 10 );
      phoneLabel = new JLabel();
      phoneTextField = new JTextField( 10 );
      queryPanel = new JPanel();
      queryLabel = new JLabel();
      queryTextField = new JTextField( 10 );
      queryButton = new JButton();
      browseButton = new JButton();
      insertButton = new JButton();
      updateButton = new JButton();
            deleteButton = new JButton();

           setLayout( new FlowLayout( FlowLayout.CENTER, 10, 10 ) );
      setSize( 400, 400 );
      setResizable( false );

      navigatePanel.setLayout(
         new BoxLayout( navigatePanel, BoxLayout.X_AXIS ) );

      previousButton.setText( "Previous" );
      previousButton.setEnabled( false );
      previousButton.addActionListener(
         new ActionListener()
         {
            public void actionPerformed( ActionEvent evt )
            {
               previousButtonActionPerformed( evt );
            } // end method actionPerformed
         } // end anonymous inner class
      ); // end call to addActionListener

      navigatePanel.add( previousButton );
      navigatePanel.add( Box.createHorizontalStrut( 10 ) );

      indexTextField.setHorizontalAlignment(
         JTextField.CENTER );
      indexTextField.addActionListener(
         new ActionListener()
         {
            public void actionPerformed( ActionEvent evt )
            {
               indexTextFieldActionPerformed( evt );
            } // end method actionPerformed
         } // end anonymous inner class
      ); // end call to addActionListener

      navigatePanel.add( indexTextField );
      navigatePanel.add( Box.createHorizontalStrut( 10 ) );

      ofLabel.setText( "of" );
      navigatePanel.add( ofLabel );
      navigatePanel.add( Box.createHorizontalStrut( 10 ) );

      maxTextField.setHorizontalAlignment(
         JTextField.CENTER );
      maxTextField.setEditable( false );
      navigatePanel.add( maxTextField );
      navigatePanel.add( Box.createHorizontalStrut( 10 ) );

      nextButton.setText( "Next" );
      nextButton.setEnabled( false );
      nextButton.addActionListener(
         new ActionListener()
         {
            public void actionPerformed( ActionEvent evt )
            {
               nextButtonActionPerformed( evt );
            } // end method actionPerformed
         } // end anonymous inner class
      ); // end call to addActionListener

      navigatePanel.add( nextButton );
      add( navigatePanel );

      displayPanel.setLayout( new GridLayout( 5, 2, 4, 4 ) );

      idLabel.setText( "Address ID:" );
      displayPanel.add( idLabel );

      idTextField.setEditable( false );
      displayPanel.add( idTextField );

      firstNameLabel.setText( "First Name:" );
      displayPanel.add( firstNameLabel );
      displayPanel.add( firstNameTextField );

      lastNameLabel.setText( "Last Name:" );
      displayPanel.add( lastNameLabel );
      displayPanel.add( lastNameTextField );

      emailLabel.setText( "Email:" );
      displayPanel.add( emailLabel );
      displayPanel.add( emailTextField );

      phoneLabel.setText( "Phone Number:" );
      displayPanel.add( phoneLabel );
      displayPanel.add( phoneTextField );
      add( displayPanel );

      queryPanel.setLayout(
         new BoxLayout( queryPanel, BoxLayout.X_AXIS) );

      queryPanel.setBorder( BorderFactory.createTitledBorder(
         "Find an entry by last name" ) );
      queryLabel.setText( "Last Name:" );
      queryPanel.add( Box.createHorizontalStrut( 5 ) );
      queryPanel.add( queryLabel );
      queryPanel.add( Box.createHorizontalStrut( 10 ) );
      queryPanel.add( queryTextField );
      queryPanel.add( Box.createHorizontalStrut( 10 ) );

      queryButton.setText( "Find" );
      queryButton.addActionListener(
         new ActionListener()
         {
            public void actionPerformed( ActionEvent evt )
            {
               queryButtonActionPerformed( evt );
            } // end method actionPerformed
         } // end anonymous inner class
      ); // end call to addActionListener

      queryPanel.add( queryButton );
      queryPanel.add( Box.createHorizontalStrut( 5 ) );
      add( queryPanel );

      browseButton.setText( "Browse All Entries" );
      browseButton.addActionListener(
         new ActionListener()
         {
            public void actionPerformed( ActionEvent evt )
            {
               browseButtonActionPerformed( evt );
            } // end method actionPerformed
         } // end anonymous inner class
      ); // end call to addActionListener

      add( browseButton );

      insertButton.setText( "Insert New Entry" );
      insertButton.addActionListener(
         new ActionListener()
         {
            public void actionPerformed( ActionEvent evt )
            {
               insertButtonActionPerformed( evt );
            } // end method actionPerformed
         } // end anonymous inner class
      ); // end call to addActionListener

         add( insertButton );      
           
            updateButton.setText( "Update Current Entry" );
            updateButton.addActionListener(
                  new ActionListener()
                  {
                        public void actionPerformed( ActionEvent evt )
                        {
                              updateButtonActionPerformed( evt );
                        } // end method actionPerformed
                  } // end anonymous inner class
                  );// end call to ActionListener
           
            add( updateButton );
                        
                  deleteButton.setText( "Delete Current Entry" );
            deleteButton.addActionListener(
                  new ActionListener()
                  {
                        public void actionPerformed( ActionEvent evt )
                        {
                              deleteButtonActionPerformed( evt );
                        } // end method actionPerformed
                  } // end anonymous inner class
                  );// end call to ActionListener
           
            add( deleteButton );                        
            
      addWindowListener(
         new WindowAdapter()
         {  
            public void windowClosing( WindowEvent evt )
            {
               System.exit( 0 );
            } // end method windowClosing
         } // end anonymous inner class
      ); // end call to addWindowListener
     
      setVisible( true );
   } // end no-argument constructor

   // handles call when previousButton is clicked
   private void previousButtonActionPerformed( ActionEvent evt )
   {
      currentEntryIndex--;
     
      if ( currentEntryIndex < 0 )
         currentEntryIndex = numberOfEntries - 1;
     
            
            
            
      indexTextField.setText( "" + ( currentEntryIndex + 1 ) );
      indexTextFieldActionPerformed( evt );  
   } // end method previousButtonActionPerformed

   // handles call when nextButton is clicked
   private void nextButtonActionPerformed( ActionEvent evt )
   {
      currentEntryIndex++;
     
      if ( currentEntryIndex >= numberOfEntries )
         currentEntryIndex = 0;
     
      indexTextField.setText( "" + ( currentEntryIndex + 1 ) );
      indexTextFieldActionPerformed( evt );
   } // end method nextButtonActionPerformed

   // handles call when queryButton is clicked
   private void queryButtonActionPerformed( ActionEvent evt )
   {
      results =
         personQueries.getPeopleByLastName( queryTextField.getText() );
      numberOfEntries = results.size();
     
      if ( numberOfEntries != 0 )
      {
         currentEntryIndex = 0;
         currentEntry = results.get( currentEntryIndex );
         idTextField.setText("" + currentEntry.getAddressID() );
         firstNameTextField.setText( currentEntry.getFirstName() );
         lastNameTextField.setText( currentEntry.getLastName() );
         emailTextField.setText( currentEntry.getEmail() );
         phoneTextField.setText( currentEntry.getPhoneNumber() );
         maxTextField.setText( "" + numberOfEntries );
         indexTextField.setText( "" + ( currentEntryIndex + 1 ) );
         nextButton.setEnabled( true );
         previousButton.setEnabled( true );
      } // end if
      else
         browseButtonActionPerformed( evt );
   } // end method queryButtonActionPerformed

   // handles call when a new value is entered in indexTextField
   private void indexTextFieldActionPerformed( ActionEvent evt )
   {
      currentEntryIndex =
         ( Integer.parseInt( indexTextField.getText() ) - 1 );
     
      if ( numberOfEntries != 0 && currentEntryIndex < numberOfEntries )
      {
         currentEntry = results.get( currentEntryIndex );
         idTextField.setText("" + currentEntry.getAddressID() );
         firstNameTextField.setText( currentEntry.getFirstName() );
         lastNameTextField.setText( currentEntry.getLastName() );
         emailTextField.setText( currentEntry.getEmail() );
         phoneTextField.setText( currentEntry.getPhoneNumber() );
         maxTextField.setText( "" + numberOfEntries );
         indexTextField.setText( "" + ( currentEntryIndex + 1 ) );
      } // end if
    } // end method indexTextFieldActionPerformed

   // handles call when browseButton is clicked
   private void browseButtonActionPerformed( ActionEvent evt )
   {
      try
      {
         results = personQueries.getAllPeople();
         numberOfEntries = results.size();
     
         if ( numberOfEntries != 0 )
         {
            currentEntryIndex = 0;
            currentEntry = results.get( currentEntryIndex );
            idTextField.setText("" + currentEntry.getAddressID() );
            firstNameTextField.setText( currentEntry.getFirstName() );
            lastNameTextField.setText( currentEntry.getLastName() );
            emailTextField.setText( currentEntry.getEmail() );
            phoneTextField.setText( currentEntry.getPhoneNumber() );
            maxTextField.setText( "" + numberOfEntries );
            indexTextField.setText( "" + ( currentEntryIndex + 1 ) );
            nextButton.setEnabled( true );
            previousButton.setEnabled( true );
         } // end if
      } // end try
      catch ( Exception e )
      {
         e.printStackTrace();
      } // end catch
   } // end method browseButtonActionPerformed

   // handles call when insertButton is clicked
   private void insertButtonActionPerformed( ActionEvent evt )
   {
      int result = personQueries.addPerson( firstNameTextField.getText(),
         lastNameTextField.getText(), emailTextField.getText(),
         phoneTextField.getText() );
     
      if ( result == 1 )
         JOptionPane.showMessageDialog( this, "Person added!",
            "Person added", JOptionPane.PLAIN_MESSAGE );
      else
         JOptionPane.showMessageDialog( this, "Person not added!",
            "Error", JOptionPane.PLAIN_MESSAGE );
         
      browseButtonActionPerformed( evt );
   } // end method insertButtonActionPerformed
   
      private void updateButtonActionPerformed( ActionEvent evt )
      {
         int result = personQueries.updatePerson( firstNameTextField.getText(),
         lastNameTextField.getText(), emailTextField.getText(),
         phoneTextField.getText() );
            if ( result == 1 )
                  JOptionPane.showMessageDialog( this, "Person updated!",
                        "Person updated", JOptionPane.PLAIN_MESSAGE );
            else
                  JOptionPane.showMessageDialog( this, "Person not updated!",
                        "Person not updated", JOptionPane.PLAIN_MESSAGE );
                       
            updateButtonActionPerformed( evt );
      } // end method updateButtonActionPerformed
            
            private void   deleteButtonActionPerformed(ActionEvent evt )
      {
           int result = personQueries.deletePerson(Integer.parseInt(idTextField.getText()) );
     
      if ( result == 1 )
         JOptionPane.showMessageDialog( this, "Person Deleted!",
            "Person Data Updated!", JOptionPane.PLAIN_MESSAGE );
      else
         JOptionPane.showMessageDialog( this, "Person Data not Deleted!",
            "Error", JOptionPane.PLAIN_MESSAGE );
            browseButtonActionPerformed(evt);
      } // end method deleteButtonActionPerformed
   
      public static void main( String args[] )
   {
      new AddressBookDisplay();
   } // end method main
} //
import java.sql.*;
import java.util.List;
import java.util.ArrayList;

public class PersonQueries
{
   private static String URL = "jdbc:derby:AddressBook;create=true";

   private static final String USERNAME = "deitel";
   private static final String PASSWORD = "deitel";

   private Connection connection = null; // manages connection
   private PreparedStatement selectAllPeople = null;
   private PreparedStatement selectPeopleByLastName = null;
   private PreparedStatement insertNewPerson = null;
      private PreparedStatement updatePerson = null;
      private PreparedStatement deletePerson = null;
   // constructor
   public PersonQueries()
   {
     
            try
      {
               Class.forName("org.apache.derby.jdbc.EmbeddedDriver");      
                  
                  connection = DriverManager.getConnection( URL, USERNAME, PASSWORD );

         // create query that selects all entries in the AddressBook
                  selectAllPeople =
            connection.prepareStatement( "SELECT * FROM Addresses" );

         // create query that selects entries with a specific last name
         selectPeopleByLastName = connection.prepareStatement(
            "SELECT * FROM Addresses WHERE LastName = ?" );

         // create insert that adds a new entry into the database
         insertNewPerson = connection.prepareStatement(
            "INSERT INTO Addresses " +
            "( FirstName, LastName, Email, PhoneNumber ) " +
            "VALUES ( ?, ?, ?, ? )" );
                        
                  // create updates current entry in the database
                  updatePerson = connection.prepareStatement(
                      "UPDATE Addresses " +
                      "SET LastName = ?, " +
                      "FirstName = ?, " +
                    "PhoneNumber = ?, " +
                      "Email = ?, " +
                      "WHERE AddressID = ?");
                  
                  // delete the current entry in the database      
                  deletePerson = connection.prepareStatement(
                    "DELETE FROM Adresses " +
                    "WHERE ID = ?");      
                        } // end try
      catch ( Exception sqlException )
      {
         sqlException.printStackTrace();
         System.exit( 1 );
      } // end catch
   } // end PersonQueries constructor

   // select all of the addresses in the database
   public List< Person > getAllPeople()
   {
      List< Person > results = null;
      ResultSet resultSet = null;

      try
      {
         // executeQuery returns ResultSet containing matching entries
         resultSet = selectAllPeople.executeQuery();
         results = new ArrayList< Person >();

         while ( resultSet.next() )
         {
            results.add( new Person(
               resultSet.getInt( "addressID" ),
               resultSet.getString( "firstName" ),
               resultSet.getString( "lastName" ),
               resultSet.getString( "email" ),
               resultSet.getString( "phoneNumber" ) ) );
         } // end while
      } // end try
      catch ( SQLException sqlException )
      {
         sqlException.printStackTrace();
      } // end catch
      finally
      {
         try
         {
            resultSet.close();
         } // end try
         catch ( SQLException sqlException )
         {
            sqlException.printStackTrace();
            close();
         } // end catch
      } // end finally

      return results;
   } // end method getAllPeople

   // select person by last name
   public List< Person > getPeopleByLastName( String name )
   {
      List< Person > results = null;
      ResultSet resultSet = null;

      try
      {
         selectPeopleByLastName.setString( 1, name ); // specify last name

         // executeQuery returns ResultSet containing matching entries
         resultSet = selectPeopleByLastName.executeQuery();

         results = new ArrayList< Person >();

         while ( resultSet.next() )
         {
            results.add( new Person(
                 resultSet.getInt( "addressID" ),
               resultSet.getString( "firstName" ),
               resultSet.getString( "lastName" ),
               resultSet.getString( "email" ),
               resultSet.getString( "phoneNumber" ) ) );
         } // end while
      } // end try
      catch ( SQLException sqlException )
      {
         sqlException.printStackTrace();
      } // end catch
      finally
      {
         try
         {
            resultSet.close();
         } // end try
         catch ( SQLException sqlException )
         {
            sqlException.printStackTrace();
            close();
         } // end catch
      } // end finally

      return results;
   } // end method getPeopleByName

   // add an entry
   public int addPerson(
      String fname, String lname, String email, String num )
   {
      int result = 0;

      // set parameters, then execute insertNewPerson
      try
      {
         insertNewPerson.setString( 1, fname );
         insertNewPerson.setString( 2, lname );
         insertNewPerson.setString( 3, email );
         insertNewPerson.setString( 4, num );

         // insert the new entry; returns # of rows updated
         result = insertNewPerson.executeUpdate();
      } // end try
      catch ( SQLException sqlException )
      {
         sqlException.printStackTrace();
         close();
      } // end catch

      return result;
   } // end method addPerson
      
      public int updatePerson(
                  String fname, String lname, String email, String num )
      {
            int result = 0;
                        
      try{
                      updatePerson.setString(1, fname );
            updatePerson.setString(2, lname );
            updatePerson.setString(3, email );
            updatePerson.setString(4, num );
                   
                        // update the current entry;
                        result = updatePerson.executeUpdate();
        } // end try
              catch (SQLException e)
                     {
            e.printStackTrace();
        } // end catch
            return result;
      } // end updatePerson
      
      public int deletePerson( int uid )
   {
      int result = 0;
     
      // set parameterss, then execute editNewPersons
      try
      {
         deletePerson.setInt( 1, uid );

         // modify the  entry; returns # of rows updated
         result = deletePerson.executeUpdate();
      } // end try
      catch ( SQLException sqlException )
      {
         sqlException.printStackTrace();
         close();
      } // end catch
     
      return result;
   } // end method updatePerson
   // close the database connection
   public void close()
   {
      try
      {
         connection.close();
      } // end try
      catch ( SQLException sqlException )
      {
         sqlException.printStackTrace();
      } // end catch
   } // end method close
} // end class PersonQueries




address.sql
derby.log