Deci sa incep cu niste secvente de cod:
//Coada generica
// MainFrame.java
package pack;
import javax.swing.*;
import pack.Queue;
import java.awt.*;
import java.awt.event.*;
public class MainFrame extends WindowAdapter implements ActionListener {
private int maxX = 500;
private int maxY = 500;
protected JTextField textField;
//stiva:
Queue<String> coada = new Queue<String>(10);
//initializare MainFrame
public MainFrame() {
Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
maxX = screenSize.width – 50;
maxY = screenSize.height – 50;
}
//Butoane
protected JComponent createButtonPane() {
JButton b1 = new JButton(“Poll”);
b1.setActionCommand(“poll”);
b1.addActionListener(this);
JButton b2 = new JButton(“Offer”);
b2.setActionCommand(“offer”);
b2.addActionListener(this);
JButton b3 = new JButton(“Element”);
b3.setActionCommand(“element”);
b3.addActionListener(this);
JButton b4 = new JButton(“Peek”);
b4.setActionCommand(“peek”);
b4.addActionListener(this);
JButton b5 = new JButton(“Remove”);
b5.setActionCommand(“remove”);
b5.addActionListener(this);
JButton b6 = new JButton(“Add”);
b6.setActionCommand(“add”);
b6.addActionListener(this);
textField = new JTextField(20);
textField.addActionListener(this);
//panel cu butoane
JPanel pane = new JPanel();
pane.setBorder(BorderFactory.createEmptyBorder(5,5,5,5));
pane.add(b1);
pane.add(b2);
pane.add(b3);
pane.add(b4);
pane.add(b5);
pane.add(b6);
pane.add(textField);
return pane;
}
//Handle action event
public void actionPerformed(ActionEvent e) {
if (“add”.equals(e.getActionCommand())) {
try {
coada.add(textField.getText());
System.out.print(/*”S-a executat add in coada: ” +*/ textField.getText());
}catch(QueueOverflow ex)
{
System.err.println(“Caught QueueOverflow exception: “ + ex.getMessage());
}
}
else if(“offer”.equals(e.getActionCommand())) {
coada.offer(textField.getText());
System.out.print(/*”S-a executat offer in coada: ” +*/ textField.getText());
}
else if(“element”.equals(e.getActionCommand())){
try {
System.out.print(“Element: “ + coada.element());
}catch(QueueEmpty ex)
{
System.err.println(“Caught QueueEmpty exception: “ + ex.getMessage());
}
}
else if(“peek”.equals(e.getActionCommand())){
System.out.print(“Peek: “ + coada.peek());
}
else if(“remove”.equals(e.getActionCommand())) {
try {
System.out.print(“Remove: “ + coada.remove());
}catch(QueueEmpty ex)
{
System.err.println(“Caught QueueEmpty exception: “ + ex.getMessage());
}
}
else if(“poll”.equals(e.getActionCommand())){
System.out.print(“Poll: “ + coada.poll());
}
}
private static void createAndShowGUI(){
//Create and set up the window.
JFrame frame = new JFrame(“Coada Generica”);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
MainFrame demo = new MainFrame();
//Add components to it.
Container contentPane = frame.getContentPane();
contentPane.add(demo.createButtonPane(),BorderLayout.PAGE_END);
//Display the window.
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
}
——————————————————————-
//Queue.java
package pack;
import pack.QueueInterface;
// My Exceptions
class QueueOverflow extends Exception {
public QueueOverflow() {}
public QueueOverflow(String msg) {
super(msg);
}
}
class QueueEmpty extends Exception {
public QueueEmpty() {}
public QueueEmpty(String msg) {
super(msg);
}
}
public class Queue<T> implements QueueInterface<T> {
private T coada[];
private int front;
private int rear;
private int nItems;
int dim;
//Constructor
public Queue(int dim)
{
coada = (T[])new Object[dim];
this.dim = dim;
front = 0;
rear = -1;
nItems = 0;
}
//Add & Offer
public void add(T item) throws QueueOverflow {
if(rear==dim-1)
throw new QueueOverflow(“Coada plina”);
else {
coada[++rear]=item;
nItems++;
}
}
public boolean offer(T item) {
if(rear==dim-1)
return false;
else {
coada[++rear]=item;
nItems++;
return true;
}
}
//Element & Peek
public T element() throws QueueEmpty {
T temp = coada[front];
if(front==dim – 1)
throw new QueueEmpty(“Coada goala”);
else {
nItems–;
return temp ;
}
}
public T peek() {
T temp = coada[front];
if(front==dim – 1)
return null;
else {
nItems–;
return temp ;
}
}
//Pop & Poll
public T remove() throws QueueEmpty {
T temp = coada[front++];
if(front==dim)
throw new QueueEmpty(“Coada goala”);
else {
nItems–;
return temp ;
}
}
public T poll() {
T temp = coada[front++];
if(front==dim)
return null;
else {
nItems–;
return temp ;
}
}
}
———————————————————————————————-
//QueueInterface.java
package pack;
public interface QueueInterface<T> {
void add (T item)throws QueueOverflow;
boolean offer(T item);
T element()throws QueueEmpty;
T peek();
T remove()throws QueueEmpty;
T poll();
}
————————————————————–
________________________________________________________________________
//stack
//StackInterface.java
package pack;
import pack.StackEmpty;
import pack.StackOverflow;
public interface StackInterface<T> {
void push (T item)throws StackOverflow;
boolean offer(T item);
T element()throws StackEmpty;
T peek();
T pop()throws StackEmpty;
T poll();
}
//Stack.java
package pack;
import pack.StackEmpty;
import pack.StackInterface;
import pack.StackOverflow;
// My Exceptions
class StackOverflow extends Exception {
public StackOverflow() {}
public StackOverflow(String msg) {
super(msg);
}
}
class StackEmpty extends Exception {
public StackEmpty() {}
public StackEmpty(String msg) {
super(msg);
}
}
public class Stack<T> implements StackInterface<T> {
private T stiva[];
int dim;
int k;
//Constructor
public Stack(int dim)
{
stiva =(T[])new Object[dim];
this.dim=dim;
k=-1;
}
//Push & Offer
public void push(T item) throws StackOverflow {
if(k==dim)
throw new StackOverflow(“Stiva plina”);
else
stiva[++k]=item;
}
public boolean offer(T item) {
if(k==dim)
return false;
else {
stiva[++k]=item;
return true;
}
}
//Element & Peek
public T element() throws StackEmpty {
if(k==-1)
throw new StackEmpty(“Stiva goala”);
else
return stiva[k];
}
public T peek() {
if (k==-1)
return null;
else return stiva[k];
}
//Pop & Poll
public T pop() throws StackEmpty {
if(k==-1)
throw new StackEmpty(“Stiva goala”);
return stiva[k--];
}
public T poll() {
if (k==-1)
return null;
else return stiva[k--];
}
}
—————————————————————-
//MainFrame.java
package pack;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class MainFrame extends WindowAdapter implements ActionListener {
private int maxX = 500;
private int maxY = 500;
protected JTextField textField;
//stiva:
Stack<String> stiva = new Stack<String>(10);
//initializare MainFrame
public MainFrame() {
Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
maxX = screenSize.width – 50;
maxY = screenSize.height – 50;
}
//Butoane
protected JComponent createButtonPane() {
JButton b1 = new JButton(“Poll”);
b1.setActionCommand(“poll”);
b1.addActionListener(this);
JButton b2 = new JButton(“Offer”);
b2.setActionCommand(“offer”);
b2.addActionListener(this);
JButton b3 = new JButton(“Element”);
b3.setActionCommand(“element”);
b3.addActionListener(this);
JButton b4 = new JButton(“Peek”);
b4.setActionCommand(“peek”);
b4.addActionListener(this);
JButton b5 = new JButton(“Pop”);
b5.setActionCommand(“pop”);
b5.addActionListener(this);
JButton b6 = new JButton(“Push”);
b6.setActionCommand(“push”);
b6.addActionListener(this);
textField = new JTextField(20);
textField.addActionListener(this);
//panel cu butoane
JPanel pane = new JPanel();
pane.setBorder(BorderFactory.createEmptyBorder(5,5,5,5));
pane.add(b1);
pane.add(b2);
pane.add(b3);
pane.add(b4);
pane.add(b5);
pane.add(b6);
pane.add(textField);
return pane;
}
//Handle action event
public void actionPerformed(ActionEvent e) {
if (“push”.equals(e.getActionCommand())) {
try {
stiva.push(textField.getText());
System.out.print(/*”S-a executat push in stiva: ” +*/ textField.getText());
}catch(StackOverflow ex)
{
System.err.println(“Caught StackOverflow exception: “ + ex.getMessage());
}
}
else if(“offer”.equals(e.getActionCommand())) {
stiva.offer(textField.getText());
System.out.print(/*”S-a executat offer in stiva: ” +*/ textField.getText());
}
else if(“element”.equals(e.getActionCommand())){
try {
System.out.print(“Element: “ + stiva.element());
}catch(StackEmpty ex)
{
System.err.println(“Caught StackEmpty exception: “ + ex.getMessage());
}
}
else if(“peek”.equals(e.getActionCommand())){
System.out.print(“Peek: “ + stiva.peek());
}
else if(“pop”.equals(e.getActionCommand())) {
try {
System.out.print(“Pop: “ + stiva.pop());
}catch(StackEmpty ex)
{
System.err.println(“Caught StackEmpty exception: “ + ex.getMessage());
}
}
else if(“poll”.equals(e.getActionCommand())){
System.out.print(“Poll: “ + stiva.poll());
}
}
private static void createAndShowGUI(){
//Create and set up the window.
JFrame frame = new JFrame(“Stiva generica”);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
MainFrame demo = new MainFrame();
//Add components to it.
Container contentPane = frame.getContentPane();
contentPane.add(demo.createButtonPane(),BorderLayout.PAGE_END);
//Display the window.
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
}
