// Tutorial 5: Inventory.java
// Calculates the number of items in a shipment based on the number
// of cartons received and the number of items per carton.
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class Inventory extends JFrame
{
// JLabel and JTextField for cartons per shipment
private JLabel cartonsJLabel;
private JTextField cartonsJTextField;
// JLabel and JTextField for items per carton
private JLabel itemsJLabel;
private JTextField itemsJTextField;
// JLabel and JTextField for total items per shipment
private JLabel totalJLabel;
private JTextField totalResultJTextField;
// JButton to initiate calculation of total items per shipment
private JButton calculateJButton;
// no-argument constructor
public Inventory()
{
createUserInterface();
}
// create and position GUI components; register event handlers
public void createUserInterface()
{
// get content pane for attaching GUI components
Container contentPane = getContentPane();
// enable explicit positioning of GUI components
contentPane.setLayout( null );
// set up cartonsJLabel
cartonsJLabel = new JLabel();
cartonsJLabel.setText( "Cartons per shipment:" );
cartonsJLabel.setBounds( 16, 16, 130, 21 );
contentPane.add( cartonsJLabel );
// set up cartonsJTextField
cartonsJTextField = new JTextField();
cartonsJTextField.setText( "0" );
cartonsJTextField.setBounds( 148, 16, 40, 21 );
cartonsJTextField.setHorizontalAlignment( JTextField.RIGHT );
contentPane.add( cartonsJTextField );
cartonsJTextField.addKeyListener(
new KeyAdapter() // anonymous inner class
{
// method called when user types in cartonsJTextField
public void keyPressed( KeyEvent event )
{
cartonsJTextFieldKeyPressed( event );
}
} // end anonymous inner class
); // end call to addKeyListener
// set up itemsJLabel
itemsJLabel = new JLabel();
itemsJLabel.setText( "Items per carton:" );
itemsJLabel.setBounds( 16, 48, 104, 21 );
contentPane.add( itemsJLabel );
// set up itemsJTextField
itemsJTextField = new JTextField();
itemsJTextField.setText( "0" );
itemsJTextField.setBounds( 148, 48, 40, 21 );
itemsJTextField.setHorizontalAlignment( JTextField.RIGHT );
contentPane.add( itemsJTextField );
itemsJTextField.addKeyListener(
new KeyAdapter() // anonymous inner class
{
// method called when user types in itemsJTextField
public void keyPressed( KeyEvent event )
{
itemsJTextFieldKeyPressed( event );
}
} // end anonymous inner class
); // end call to addKeyListener
// set up totalJLabel
totalJLabel = new JLabel();
totalJLabel.setText( "Total:" );
totalJLabel.setBounds( 204, 16, 40, 21 );
contentPane.add( totalJLabel );
// set up totalResultJTextField
totalResultJTextField = new JTextField();
totalResultJTextField.setBounds( 244, 16, 86, 21 );
totalResultJTextField.setHorizontalAlignment(
JTextField.RIGHT );
totalResultJTextField.setEditable( false ); // output only
contentPane.add( totalResultJTextField );
// set up calculateJButton
calculateJButton = new JButton();
calculateJButton.setText( "Calculate Total" );
calculateJButton.setBounds( 204, 48, 126, 24 );
contentPane.add( calculateJButton );
calculateJButton.addActionListener(
new ActionListener() // anonymous inner class
{
// method called when calculateJButton is pressed
public void actionPerformed( ActionEvent event )
{
calculateJButtonActionPerformed( event );
}
} // end anonymous inner class
); // end call to addActionListener
// set properties of application's window
setTitle( "Inventory" ); // set title bar text
setSize( 354, 112 ); // set window size
setVisible( true ); // display window
} // end method createUserInterface
// calculate the total items in the shipment
private void calculateJButtonActionPerformed( ActionEvent event )
{
// declare variables
int cartons; // stores number of cartons in shipment
int items; // stores number of items per carton
int result; // stores product of cartons and items
// retrieve numbers from JTextFields
cartons = Integer.parseInt( cartonsJTextField.getText() );
items = Integer.parseInt( itemsJTextField.getText() );
// multiply values input
result = cartons * items;
// display result in totalResultJTextField
totalResultJTextField.setText( String.valueOf( result ) );
} // end method calculateJButtonActionPerformed
// clear totalResultJTextField because the value is now invalid
private void cartonsJTextFieldKeyPressed( KeyEvent event )
{
totalResultJTextField.setText( "" ); // clear output JTextField
} // end method cartonsJTextFieldKeyPressed
// clear totalResultJTextField because the value is now invalid
private void itemsJTextFieldKeyPressed( KeyEvent event )
{
totalResultJTextField.setText( "" ); // clear output JTextField
} // end method itemsJTextFieldKeyPressed
// main method
public static void main( String[] args )
{
Inventory application = new Inventory();
application.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
} // end method main
} // end class Inventory
/**************************************************************************
* (C) Copyright 1992-2004 by Deitel & Associates, Inc. and *
* Pearson Education, Inc. All Rights Reserved. *
* *
* DISCLAIMER: The authors and publisher of this book have used their *
* best efforts in preparing the book. These efforts include the *
* development, research, and testing of the theories and programs *
* to determine their effectiveness. The authors and publisher make *
* no warranty of any kind, expressed or implied, with regard to these *
* programs or to the documentation contained in these books. The authors *
* and publisher shall not be liable in any event for incidental or *
* consequential damages in connection with, or arising out of, the *
* furnishing, performance, or use of these programs. *
**************************************************************************/
