ActionListener Example

import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
import java.text.DecimalFormat;
import java.util.ArrayList;


public class makine extends JApplet{

 
 private int counter = 0;
 
 
 private ArrayList<String> liste;
 private String[] yazi;
 private JButton one,two,three,four,five,
 six,seven,eight,nine,zero,
 arti,eksi,bolu,carpi,CE,esit;
 
 
 
 private JTextField ekran;
 private JLabel yazar;
 private DecimalFormat dec;
 
 public String ToString(Double d)
 {
  return d.toString();
 }
 //@override
 public void init()
 { 
  yazi = new String[11];
  liste = new ArrayList<String>();
  for(int i = 0;i<11;i++){
   yazi[i] = "";
  }
  ActionHandler handler = new ActionHandler();
  Container container = this.getContentPane();
  container.setLayout(new FlowLayout(1,8,2));
  
  
  
  dec = new DecimalFormat("0.000");
  one = new JButton();
  one.setText("1");
  one.setSize(20, 20);
  one.setLocation(40, 40);
  container.add(one);
  one.addActionListener(handler);
  
  
  two = new JButton();
  two.setText("2");
  two.setSize(20, 20);
  two.setLocation(40, 40);
  container.add(two);
  two.addActionListener(handler);
  
  three = new JButton();
  three.setText("3");
  three.setSize(20, 20);
  three.setLocation(70, 40);
  container.add(three);
  three.addActionListener(handler);
  
  arti = new JButton();
  arti.setText("+");
  arti.setSize(20, 20);
  arti.setLocation(100, 40);
  container.add(arti);
  arti.addActionListener(handler);
  
  four = new JButton();
  four.setText("4");
  four.setSize(20, 20);
  four.setLocation(10, 70);
  container.add(four);
  four.addActionListener(handler);
  
  five = new JButton();
  five.setText("5");
  five.setSize(20, 20);
  five.setLocation(40, 70);
  container.add(five);
  five.addActionListener(handler);
  
  six = new JButton();
  six.setText("6");
  six.setSize(20, 20);
  six.setLocation(70, 70);
  container.add(six);
  six.addActionListener(handler);
  
  eksi = new JButton();
  eksi.setText("-");
  eksi.setSize(20, 20);
  eksi.setLocation(10, 70);
  container.add(eksi);
  eksi.addActionListener(handler);
  
  seven = new JButton();
  seven.setText("7");
  seven.setSize(20, 20);
  seven.setLocation(10, 100);
  container.add(seven);
  seven.addActionListener(handler);
  

  
  
  eight = new JButton();
  eight.setText("8");
  eight.setSize(20, 20);
  eight.setLocation(40, 100);
  container.add(eight);
  eight.addActionListener(handler);
  
  nine = new JButton();
  nine.setText("9");
  nine.setSize(20, 20);
  nine.setLocation(70, 100);
  container.add(nine);
  nine.addActionListener(handler);
  
  carpi = new JButton();
  carpi.setText("x");
  carpi.setSize(20, 20);
  carpi.setLocation(100, 130);
  container.add(carpi);
  carpi.addActionListener(handler);
  
  CE = new JButton();
  CE.setText("CE");
  CE.setSize(20, 20);
  CE.setLocation(10, 100);
  container.add(CE);
  CE.addActionListener(handler);
  
  zero = new JButton();
  zero.setText("0");
  zero.setSize(20, 20);
  zero.setLocation(40, 130);
  container.add(zero);
  zero.addActionListener(handler);
  
  
  
  
  bolu = new JButton();
  bolu.setText("/");
  bolu.setSize(20, 20);
  bolu.setLocation(100, 100);
  container.add(bolu);
  bolu.addActionListener(handler);
  
  
  
  esit = new JButton();
  esit.setText("=");
  esit.setSize(20, 20);
  esit.setLocation(70, 100);
  container.add(esit);
  esit.addActionListener(handler);
  
  ekran = new JTextField(15);
  ekran.setText(" ");
  ekran.setEditable(false);
  ekran.setDisabledTextColor(Color.BLUE );
  ekran.setVisible(true);
  ekran.setAlignmentY(JTextField.RIGHT_ALIGNMENT);
  ekran.setHorizontalAlignment(JTextField.RIGHT);
  ekran.setLocation(10,10);
  container.add(ekran);
  ekran.addActionListener(handler);
  
  yazar = new JLabel("Tested and Programmed by BY");
  container.add(yazar);
  
 }
 //inner class
 private class ActionHandler implements ActionListener
 {
  public void actionPerformed(ActionEvent event)
  {
   if(event.getSource() == one){
    if(counter<11){
     yazi[counter]+="1";
     ekran.setText(yazi[counter]);
    }else ;
   }if(event.getSource() == two){
    if(counter<11){
     yazi[counter]+="2";
     ekran.setText(yazi[counter]);
    }else ;
   }if(event.getSource() == three){
    if(counter<11){
     yazi[counter]+="3";
     ekran.setText(yazi[counter]);
    }else;
   }if(event.getSource() == four){
    if(counter<11){
     yazi[counter]+= "4";
     ekran.setText(yazi[counter]);
    }else;
   }if(event.getSource() == five){
    if(counter<11){
     yazi[counter] += "5";
     ekran.setText(yazi[counter]);
    }else;
   }if(event.getSource() == six){
    if(counter<11){
     yazi[counter] += "6";
     ekran.setText(yazi[counter]);
    }else;
   }if(event.getSource() == seven){
    if(counter<11){
     yazi[counter] += "7";
     ekran.setText(yazi[counter]);
    }else;
   }if(event.getSource() == eight){
    if(counter<11){
     yazi[counter] += "8";
     ekran.setText(yazi[counter]);
    }else;
   }if(event.getSource() == nine){
    if(counter<11){
     yazi[counter] += "9";
     ekran.setText(yazi[counter]);
    }else;
   }if(event.getSource() == zero){
    if(counter<11){
     yazi[counter] += "0";
     ekran.setText(yazi[counter]);
    }else;
   }if(event.getSource() == arti){
    try{
    if(Double.parseDouble(yazi[counter])>=0){
    counter++;
    yazi[counter] = "+";
    counter++;
    }else;
    }catch(Exception e){
     ekran.setText("Syntax Error");
    }
   }if(event.getSource() == eksi){
    try{
    if(Double.parseDouble(yazi[counter])>=0){
    counter++;
    yazi[counter] = "-";
    counter++;
    }else;
    }catch(Exception e){
     ekran.setText("Syntax Error");
    }
   }if(event.getSource() == bolu){
    try{
    if(Double.parseDouble(yazi[counter])>=0){
    counter++;
    yazi[counter] = "/";
    counter++;
    }else;
    }catch(Exception e){
     ekran.setText("Syntax Error");
    }
   }if(event.getSource() == carpi){
    try{
    if(Double.parseDouble(yazi[counter])>=0){
    counter++;
    yazi[counter] = "*";
    counter++;
    }
    }catch(Exception e){
     ekran.setText("Syntax Error");
    }
   }if(event.getSource() == CE){
    for(int i = 0;i<11;i++)
     yazi[i] = "";
     ekran.setText("");
     counter = 0;
   }if(event.getSource() == esit){
    //try{
    for(int i = 0;i<11;i++){
     liste.add(i,yazi[i]);
    }
    for(int i = 0;i<11;i++){
     try{
     if(yazi[i]=="/"){
       
     yazi[i] = ToString(Double.parseDouble(yazi[i-1])/Double.parseDouble(yazi[i+1]));
       yazi[i-1] = yazi[i];
       yazi[i+1] = yazi[i];
       liste.remove(0);
       liste.add(0,yazi[i]);
      }
     }catch(Exception e){
      ekran.setText("Syntax Error");
      counter = 0;
     }
    }
    for(int i = 0;i<11;i++){
     try{ 
     if(yazi[i]=="*"){
           yazi[i] = ToString(Double.parseDouble(yazi[i-1])*Double.parseDouble(yazi[i+1]));
       yazi[i-1] = yazi[i];
       yazi[i+1] = yazi[i];
       liste.remove(0);
       liste.add(0,yazi[i]);
       
      }
     }
     catch(Exception e){
      ekran.setText("Syntax Error");
      counter = 0;
     }
    }
    for(int i = 0;i<11;i++){
     try{
     if(yazi[i]=="+"){
                         yazi[i] = ToString(Double.parseDouble(yazi[i-1])+Double.parseDouble(yazi[i+1]));
       yazi[i-1] = yazi[i];
       yazi[i+1] = yazi[i];
       liste.remove(0);
       liste.add(0,yazi[i]);
      } 
     }
     catch(Exception e){
      ekran.setText("Syntax Error");
      counter = 0;
     }
    }
    for(int i = 0;i<11;i++){
     try{
     if(yazi[i]=="-"){
        
    yazi[i] = ToString(Double.parseDouble(yazi[i-1])-Double.parseDouble(yazi[i+1]));
       yazi[i-1] = yazi[i];
       yazi[i+1] = yazi[i];
       liste.remove(0);
       liste.add(0,yazi[i]);
      }
     }
     catch(Exception e){
      ekran.setText("Syntax Error");
      counter = 0;
     } 
    } 
     if(liste.isEmpty()){
      ekran.setText("Syntax Error");
      counter = 0;}
     else{
         if(liste.get(0)!="")
                              ekran.setText(liste.get(0).toString());
     }
     counter = 0;
     for(int i = 0;i<11;i++)
      yazi[i] = "";
     if(!liste.isEmpty())
      liste.clear();
      
    /*}catch(Exception e){
     ekran.setText("Syntax Error");
    }*/
   }
   
  }
 } 
}

PingPong Game in Java

Board.java 

 

import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import javax.swing.ImageIcon;
import javax.swing.JPanel;
import javax.swing.Timer;
public class Board extends JPanel implements ActionListener{
 
 private final int width = 600;
 private final int height = 600;
 
 private int delay = 30;//time delay to update
 private int board_x;//board x location
 private int board_y;//board y location
 private int ball_x;//ball x location
 private int ball_y;//ball y location
 private float ball_xv;//ball x violation
 private float ball_yv;//ball y violation
 
 //conditions
 private boolean running = true;
 private boolean contin= true; 
 private boolean tryagain = false;
 
 //for keyboard 
 private boolean pause = false;
 private boolean left = false;
 private boolean right = false;
 
 //for mouse motions
 private boolean dragged = false;
 private int howfarx = 0; //how far mouse click x coordinate from object's x coordinate
 
 
 private Image ball;
 private Image board;
 private Timer timer;
 private Image background;
 
 private String msg = "presss";
 
 
 public Board()
 {
  addKeyListener(new TAdapter()); 
  addMouseMotionListener(new MAdapter());
  addMouseListener(new MAdapter());
  setBackground(Color.white);
  load();
  setFocusable(true);
  init();
 }
 public void load()
 {
  board = new ImageIcon("C:\\javapics\\board.png").getImage();
  ball = new ImageIcon("C:\\javapics\\ae.png").getImage();
  background = new ImageIcon("C:\\javapics\\backgroud.png").getImage();
 }
 public void actionPerformed(ActionEvent e) {
  
  if(running)
  {
      if(contin)
      {
       ballmoving();
       boardmove();
       lose();
      }
      
  }
   repaint();
 }
 public void start()
 {
  ball_xv = -0.4f;
  ball_yv = -0.3f;
  board_x = 240;
  board_y = 580;
  ball_x = 300;
  ball_y = 240;
 }
 public void init()
 {
  start();
  timer = new Timer(delay,this);
  timer.start();
 }
 public void paint(Graphics g)
 {
  super.paint(g);
  if(contin)
  {
   g.drawImage(ball, ball_x, ball_y,this);
   g.drawImage(board, board_x, board_y,this);
   Toolkit.getDefaultToolkit().sync();
   g.dispose();
  }
  if(tryagain)
  {
   String msg2 = "Press Enter to try again";
         Font small = new Font("Arial", Font.BOLD, 15);

         g.setColor(Color.black);
         g.setFont(small);
         g.drawString(msg2,200,300);
         
  }
  if(pause)
  {
   String msg2 = "Pause! Press Space to continue";
         Font small = new Font("Helvetica", Font.BOLD, 15);

         g.setColor(Color.black);
         g.setFont(small);
         g.drawString(msg2,200,300);
         
  }
  if(!running)
  { 
   g.drawImage(background, 0, 0,this);
  }
  
 }
 public void lose()
 {
  if(ball_y + 20 > height)
  { 
   contin = false;
   tryagain = true;
   
  }
  
 }
 public void ballmoving()
 {
  
  if(ball_x < 1)
   ball_xv = Math.abs(ball_xv);
  else if((ball_x + 20) > (width-21))
   ball_xv = -Math.abs(ball_xv);
  
  if(ball_y < 1)
   ball_yv = Math.abs(ball_yv);
  else if((ball_y+20) > (height-21))
   if(ball_x >= board_x && ball_x <= (board_x+100) )
   ball_yv = -Math.abs(ball_yv);
  
  update(delay);
  
 }
 public void update(int timedelay)//to update ball location on the screen
 {
  ball_x = (ball_x + (int)(ball_xv*delay));
  ball_y = (ball_y + (int)(ball_yv*delay));
 }
 public void boardmove()//to play with keyboard
 {
  if(left){
   board_x -= 40;
   left = false;
  }
  if(right){
   board_x += 40;
   right = false;
  }
 }
 private class MAdapter extends MouseAdapter
 {
  public void mousePressed(MouseEvent e)
  {
   int mousex = e.getX();
   int mousey = e.getY();
   if(mousex >= board_x && mousex <= (board_x+ 100))
    if(mousey >= board_y && mousey <= (board_y+100)){
     dragged = true;
     howfarx =  mousex - board_x;
   }else {
     dragged = false;
   }
  }
  public void mouseDragged(MouseEvent e)
  { 
   if(dragged){
    board_x = e.getX() - howfarx;
    
    board_x = Math.max(0, board_x);//to prevent overflow from sides
    board_x = Math.min(board_x, (width-120));/////////////////////
   }
  }
  public void mouseExited(MouseEvent e)
  {
   dragged = false;
   howfarx = 0;
  }
  public void mouseMoved   (MouseEvent e) {}  // ignore these events
  public void mouseEntered (MouseEvent e) {}  // ignore these events
  public void mouseClicked (MouseEvent e) {}  // ignore these events
  public void mouseReleased(MouseEvent e) {}  // ignore these events
 }
 private class TAdapter extends KeyAdapter
 { 
  public void keyPressed(KeyEvent e)
  {
   int key = e.getKeyCode();
   if(key == KeyEvent.VK_Z)
   { 
    msg = "pressed z";
    if((board_x - 40) >= 0)//to prevent overflow from left side from 
     left = true;
    else
     left = false;//nothing
   }
   if(key == KeyEvent.VK_X)
   {
    msg = "pressed x";
    if((board_x + 150) <= width)//to prevent overflow form right side of game area
     right = true;
    else 
     right = false;//nothing
   }
   if(key == KeyEvent.VK_ENTER){
    start();
    contin = true;
    tryagain = false;
    pause = false;
   }
   if(key == KeyEvent.VK_SPACE){
    if(!pause){
    contin = false;
    pause = true;
    tryagain = false;
    }else{
     contin = true;
     pause = false;
     tryagain = false;
    }
   }
   if(key == KeyEvent.VK_ESCAPE){
    running = false;
    contin = false;
    pause = false;
    tryagain = false;
   }
  }
 }
}

import javax.swing.*;
public class pinpong extends JApplet {

 /**
  * @param args
  */
 public pinpong()
 { 
  this.setContentPane(new Board()); 
 }
 public static void main(String[] args) {
  // TODO Auto-generated method stub
  
  JFrame window = new JFrame();
  window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        window.setSize(586, 630);
        window.setLocationRelativeTo(null);
        window.setTitle("pinpong");
        window.setContentPane(new Board());
        window.setResizable(false);
        window.setVisible(true);
 }

}