Hopefully a quick and simple question someone can assist me with. I have an inventory program that has an next, previous, first, last (these buttons work) and now I added a add, delete, modify, search and save button. Do I need to create a c:\data\inventory.dat file before implementing them? Also if someone could point me to a decent example of how to implement those buttons I would greatly appreciate it. I have searched but the tutorials I cam across didn't help me much. I have added my code in case you need to look at it for my question to make sense.
import java.util.Arrays; // program uses arrays
public class Inventory5 {
// main method begins execution of java application
public static void main(String[] args) {
System.out.println("\nCheckPoint: Inventory Part 6");
System.out.println("My DVD Collection\n");
Movie dvd = null;
Inventory inventory = new Inventory();
dvd = new Movie(1, "Superman Returns", 5, 12.99f, 2007);
System.out.println(dvd);
inventory.addMovie(dvd);
dvd = new Movie(2, "Resident Evil", 7, 14.99f, 2000);
System.out.println(dvd);
inventory.addMovie(dvd);
dvd = new Movie(3, "Hostel", 1, 21.99f, 2001);
System.out.println(dvd);
inventory.addMovie(dvd);
dvd = new Movie(4, "Office Space", 3, 15.99f, 1990);
inventory.addMovie(dvd);
System.out.println(dvd);
dvd = new Movie(5, "Rambo", 8, 11.99f, 1984);
System.out.println(dvd);
inventory.addMovie(dvd);
dvd = new Movie(6, "Spiderman", 2, 7.99f, 2005);
System.out.println(dvd);
System.out.println("\nEnd of DVD collection!\n");
inventory.addMovie(dvd);
inventory.printInventory();
GUI gui = new GUI(inventory); // Start the GUI
} // end main
} // end Inventory5
/**** Class decribes DVD while demostrating polymorphism and inheritance**/
class DVD {
private int itemNo;
private String title;
private int inStock;
private float unitPrice;
DVD(int itemNo, String title, int inStock, float unitPrice) {
this.itemNo = itemNo;
this.title = title;
this.inStock = inStock;
this.unitPrice = unitPrice;
}
public int getItemNo() { return itemNo; }
public String getTitle() { return title; }
public int getInStock() { return inStock; }
public float getUnitPrice() { return unitPrice; }
public float value() {
return inStock * unitPrice;
}
public String toString() {
return String.format("itemNo=%2d title=%-22s inStock=%3d price=$%7.2f value=$%8.2f",
itemNo, title, inStock, unitPrice, value());
}
} // end DVD
/*****class has inventory of DVDs.
* This class has methods to add and display dvds****/
class Inventory {
private final int INVENTORY_SIZE = 30;
private DVD[] items;
private int numItems;
Inventory() {
items = new Movie[INVENTORY_SIZE];
numItems = 0;
}
public int getNumItems() {
return numItems;
}
public DVD getDVD(int n) {
return items[n];
}
// Adds a Movie to the array of Movies.
public void addMovie(DVD item) {
items[numItems] = item;
++numItems;
}
// Loop through our array of Movies and add up the total value.
public double value() {
double sumOfInventory = 0.0;
for (int i = 0; i < numItems; i++)
sumOfInventory += items[i].value();
return sumOfInventory;
}
// Prints the inventory list including name, quantity, price,
// and total stock value for each item.
public void printInventory() {
System.out.println("\nMatt's DVD Inventory\n");
// If no items were found, print a message saying the inventory is empty.
if (numItems <= 0) {
System.out.println("Inventory is empty at the moment.\n");
} else {
for (int i = 0; i < numItems; i++)
System.out.printf("%3d %s\n", i, items[i]);
System.out.printf("\nTotal value in inventory is $%,.2f\n\n", value());
}
}
} // end Inventory
/**** This is a subclass that adds 5% restocking fee and new feature***/
class Movie extends DVD {
// Holds movie year and adds restocking fee
private int movieYear;
// Constructor, calls the constructor of Movie first
public Movie(int MovieID, String itemName, int quantityOnHand, float itemPrice, int year) {
super(MovieID, itemName, quantityOnHand, itemPrice);
// Pass on the values needed for creating the Movie class first thing
this.movieYear = movieYear;
}
// To set the year manually
public void setYear(int year) {
movieYear = year;
}
// Get the year of this DVD Movie
public int getMovieYear() {
return movieYear;
}
// Overrides value() in Movie class by calling the base class version and
// adding a 5% restocking fee on top
public float value() {
return super.value() + restockingFee();
}
// Simply gets the base class's value, and figures out the 5% restocking fee only
public float restockingFee() {
return super.value() * 0.05f;
}
} // end Movie
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
// GUI class creates and maintains the GUI
public class GUI extends JFrame
{
// access inventory for DVD Collection
private Inventory theInventory;
// index in the inventory of the currently displayed DVD.
// the index starts at 0, goes to the number of DVDs in the inventory minus 1
private int index = 0;
// GUI elements to display currently selected DVD information
private final JLabel itemNumberLabel = new JLabel(" Item Number:");
private JTextField itemNumberText;
private final JLabel prodnameLabel = new JLabel(" Product Name:");
private JTextField prodnameText;
private final JLabel prodpriceLabel = new JLabel(" Price:");
private JTextField prodpriceText;
private final JLabel numinstockLabel = new JLabel(" Number in Stock:");
private JTextField numinstockText;
private final JLabel valueLabel = new JLabel(" Value:");
private JTextField valueText;
private final JLabel restockingFeeLabel = new JLabel(" Restocking Fee:");
private JTextField restockingFeeText;
private final JLabel totalValueLabel = new JLabel(" Inventory Total Value:");
private JTextField totalValueText;
private JPanel buttonPanel;
private JPanel centerPanel;
private JLabel logoLabel; // the logo
private JPanel jpInstructsPanel; // the instructions
// constructor for the GUI, in charge of creating all GUI elements
GUI(Inventory inventory) {
super("Movie Inventory");
final Dimension dim = new Dimension(140, 20);
final FlowLayout flo = new FlowLayout(FlowLayout.LEFT);
JPanel jp;
// create the inventory object that will hold the product information
theInventory = inventory;
// setup the GUI
// panel setup
centerPanel = new JPanel();
centerPanel.setLayout(new BoxLayout(centerPanel, BoxLayout.Y_AXIS));
//Image and title
jpInstructsPanel = new JPanel();
jpInstructsPanel.setLayout(new FlowLayout(FlowLayout.CENTER));
ImageIcon logo = new ImageIcon("logo.gif");
JLabel jLabel = new JLabel(" DVD Inventory", logo, SwingConstants.LEFT);
jpInstructsPanel.add(jLabel);
centerPanel.add(jpInstructsPanel);
buttonPanel = new JPanel();
jp = new JPanel(flo);
itemNumberLabel.setPreferredSize(dim);
jp.add(itemNumberLabel);
itemNumberText = new JTextField(3);
itemNumberText.setEditable(false);
jp.add(itemNumberText);
centerPanel.add(jp);
jp = new JPanel(flo);
prodnameLabel.setPreferredSize(dim);
jp.add(prodnameLabel);
prodnameText = new JTextField(17);
prodnameText.setEditable(false);
jp.add(prodnameText);
centerPanel.add(jp);
jp = new JPanel(flo);
prodpriceLabel.setPreferredSize(dim);
jp.add(prodpriceLabel);
prodpriceText = new JTextField(17);
prodpriceText.setEditable(false);
jp.add(prodpriceText);
centerPanel.add(jp);
jp = new JPanel(flo);
numinstockLabel.setPreferredSize(dim);
jp.add(numinstockLabel);
numinstockText = new JTextField(5);
numinstockText.setEditable(false);
jp.add(numinstockText);
centerPanel.add(jp);
jp = new JPanel(flo);
restockingFeeLabel.setPreferredSize(dim);
jp.add(restockingFeeLabel);
restockingFeeText = new JTextField(17);
restockingFeeText.setEditable(false);
jp.add(restockingFeeText);
centerPanel.add(jp);
jp = new JPanel(flo);
valueLabel.setPreferredSize(dim);
jp.add(valueLabel);
valueText = new JTextField(17);
valueText.setEditable(false);
jp.add(valueText);
centerPanel.add(jp);
// add the overall inventory information to the panel
jp = new JPanel(flo);
totalValueLabel.setPreferredSize(dim);
jp.add(totalValueLabel);
totalValueText = new JTextField(17);
totalValueText.setEditable(false);
jp.add(totalValueText);
centerPanel.add(jp);
buttonPanel = new JPanel();
centerPanel.add(buttonPanel);
JButton firstButton = new JButton("First");
firstButton.addActionListener(new FirstButtonHandler());
buttonPanel.add(firstButton);
JButton previousButton = new JButton("Previous");
previousButton.addActionListener(new PreviousButtonHandler());
buttonPanel.add(previousButton);
JButton nextButton = new JButton("Next");
nextButton.addActionListener(new NextButtonHandler());
buttonPanel.add(nextButton);
JButton lastButton = new JButton("Last");
lastButton.addActionListener(new LastButtonHandler());
buttonPanel.add(lastButton);
JButton searchButton = new JButton("Search");
lastButton.addActionListener(new SearchButtonHandler());
buttonPanel.add(searchButton);
buttonPanel = new JPanel();
centerPanel.add(buttonPanel);
JButton addButton = new JButton("Add");
addButton.addActionListener(new AddButtonHandler());
buttonPanel.add(addButton);
JButton deleteButton = new JButton("Delete");
deleteButton.addActionListener(new DeleteButtonHandler());
buttonPanel.add(deleteButton);
JButton modifyButton = new JButton("Modify");
modifyButton.addActionListener(new ModifyButtonHandler());
buttonPanel.add(modifyButton);
JButton saveButton = new JButton("Save");
saveButton.addActionListener(new SaveButtonHandler());
buttonPanel.add(saveButton);
// add the panel to the GUI display
//setContentPane(centerPanel);
repaintGUI();
setDefaultCloseOperation(EXIT_ON_CLOSE);
setContentPane(centerPanel);
setBounds(200, 200, 450, 600);
setResizable(false);
setLocationRelativeTo(null);
setVisible(true);
}
// (re)display the GUI with current product's information
public void repaintGUI() {
Movie temp = (Movie) theInventory.getDVD(index);
if (temp != null) {
itemNumberText.setText("" + temp.getItemNo());
prodnameText.setText(temp.getTitle());
prodpriceText.setText(String.format("$%.2f", temp.getUnitPrice()));
restockingFeeText.setText(String.format("$%.2f", temp.restockingFee()));
numinstockText.setText("" + temp.getInStock());
valueText.setText(String.format("$%.2f", temp.value()));
}
totalValueText.setText(String.format("$%.2f", theInventory.value()));
}
class FirstButtonHandler implements ActionListener {
public void actionPerformed(ActionEvent e) {
index = 0;
repaintGUI();
}
}
class PreviousButtonHandler implements ActionListener {
public void actionPerformed(ActionEvent e){
--index;
if (index < 0)
index = theInventory.getNumItems()-1;
repaintGUI();
}
}
class NextButtonHandler implements ActionListener {
public void actionPerformed(ActionEvent e) {
int numItems = theInventory.getNumItems();
index = (++index) % numItems;
repaintGUI();
}
}
class LastButtonHandler implements ActionListener {
public void actionPerformed(ActionEvent e) {
int numItems = theInventory.getNumItems();
index = (numItems -1) % numItems;
repaintGUI();
}
}
class SearchButtonHandler implements ActionListener {
public void actionPerformed(ActionEvent e){
repaintGUI();
}
}
class AddButtonHandler implements ActionListener {
public void actionPerformed(ActionEvent e){
repaintGUI();
}
}
class ModifyButtonHandler implements ActionListener {
public void actionPerformed(ActionEvent e){
repaintGUI();
}
}
class SaveButtonHandler implements ActionListener {
public void actionPerformed(ActionEvent e){
repaintGUI();
}
}
class DeleteButtonHandler implements ActionListener {
public void actionPerformed(ActionEvent e){
repaintGUI();
}
}
}// end class GUI
Linear Mode
