simple java applet example of adding components

import java.awt.*;
import java.applet.*;
public class Applet3 extends Applet
{
Label l1,l2,l3;
Choice c1,c2;
List lst;
int i;
public void init()
{
l1=new Label("Select Train Name");
l2=new Label("Select Seats             ");
l3=new Label("Cause Of Visit       ");
c1=new Choice();
c1.addItem("Rajdhani Express");
c1.addItem("GT Express");
c1.addItem("Link Express");
c1.addItem("Mussoorie Express");
c1.addItem("Shatabdi Express");
c2=new Choice();
for(i=1;i<=50;i++)
c2.addItem(String.valueOf(i));
lst=new List(6);
lst.addItem("Official");
lst.addItem("Personal");
lst.addItem("Educational");
lst.addItem("Tourism");
lst.addItem("Research");
lst.addItem("WildLife");
setBackground(Color.cyan);
add(l1);
add(c1);
add(l2);
add(c2);
add(l3);
add(lst);
}
}
/*
<applet code=Applet3 height=250 width=270></applet>
*/

mutithreding in java :create thread using Runnable

class RunnableThread implements Runnable{

 Thread runner;
 public RunnableThread() {
 }

 public RunnableThread(String threadName) {
        runner = new Thread(this, threadName);   // (1) Create a new thread.
        System.out.println(runner.getName());
        runner.start();                          // (2) Start the thread.
 }

 public void run(){
  //Display info about this particular thread
  System.out.println(Thread.currentThread());
 }


}
public class RunnableExample{
 
 public static void main(String[] args){
     Thread thread1 =  new Thread(new RunnableThread(),"thread1");
     Thread thread2 =  new Thread(new RunnableThread(),"thread2");
     RunnableThread thread3 = new RunnableThread("thread3");

//Start the threads
     thread1.start();
     thread2.start();
     try{
       //delay for one second
       Thread.currentThread().sleep(1000);
     }catch(InterruptedException e){}

     //Display info about the main thread   
     System.out.println(Thread.currentThread());       
 }
}

java applet example of drawing diffrent shapes using Graphics

import java.applet.*;
import java.awt.*;
public class  fillColor extends Applet{
   public void paint(Graphics g){
      g.drawRect(300,150,200,100);
      g.setColor(Color.yellow);  
      g.fillRect( 300,150, 200, 100 );
      g.setColor(Color.magenta);
      g.drawString("Rectangle",500,150);
   }
}
 

java applet example of changing background color on button click event

import java.awt.*;
import java.awt.event.*;
import java.applet.*;
public class ColorApplet extends Applet implements ActionListener
{
 Button b1,b2,b3;

 public void init()
 {
  b1 = new Button("Red");
  b2 = new Button("Green");
  b3 = new Button("Blue");
 
  add(b1);add(b2);add(b3);
   
  b1.addActionListener(this);
  b2.addActionListener(this);
  b3.addActionListener(this);
  setBackground(Color.yellow);
 }

 public void actionPerformed(ActionEvent ae)
 {
  if(ae.getSource()==b1)
   setBackground(Color.red);
  if(ae.getSource()==b2)
   setBackground(Color.green);
  if(ae.getSource()==b3)
   setBackground(Color.blue);
 }
}


/*<applet code=ColorApplet height=300 width=300></applet>*/







 

java Applet ItemListener example

import java.awt.*;
import java.applet.*;
import java.awt.event.*;
public class ItemLis extends Applet implements ItemListener
{
Label l1,l2,l3,l4,l5,l6;
TextField t1,t2,t3,t4;
Choice ch1,ch2;
int i,qty;
float pri;
public void init()
{
l1=new Label("Item Name");
l2=new Label("Quantity    ");
l3=new Label("Price           ");
l4=new Label("Amount      ");
l5=new Label("Tax              ");
l6=new Label("With Tax     ");
t1=new TextField(15);
t2=new TextField(15);
t3=new TextField(15);
t4=new TextField(15);
ch1=new Choice();
ch1.addItem("Burger");
ch1.addItem("Pizza");
ch2=new Choice();
for(i=1;i<10;i++)
ch2.addItem(String.valueOf(i));
setBackground(Color.green);
t3.setText("12.24%");
add(l1);
add(ch1);
add(l2);
add(ch2);
add(l3);
add(t1);
add(l4);
add(t2);
add(l5);
add(t3);
add(l6);
add(t4);
ch1.addItemListener(this);
ch2.addItemListener(this);
}
public void itemStateChanged(ItemEvent ie)
{
if(ie.getSource()==ch1)
{
String inm=String.valueOf(ie.getItem());
if(inm.equals("Burger"))
{
t1.setText("Rs.75.00");
pri=75.0f;
}
else if(inm.equals("Pizza"))
{
t1.setText("Rs.125.00");
pri=125.0f;
}
}
if(ie.getSource()==ch2)
{
qty=Integer.parseInt(String.valueOf(ie.getItem()));
float amt=pri*qty;
t2.setText(String.valueOf(amt));
float tamt=amt+.1224f*amt;
t4.setText(String.valueOf(tamt));
}
}
}
/*
<applet code=ItemLis height=300 width=250></applet>
*/

java Applet LayoutExample

import java.awt.*;
import java.applet.*;
public class LayoutExample extends Applet 
    {
     Button okButton1;
     Button okButton2;
     Button okButton3;
     Button okButton4;
     Button okButton5;
     public void init()
     {
  // sets the LayoutManager to BorderLayout
        setLayout(new BorderLayout());
        okButton1 = new Button("Centered Button");
          okButton2 = new Button("Cold North");
          okButton3 = new Button("Go West");
          okButton4 = new Button("At East");
          okButton5 = new Button("Hot South");
  // always says where the component should be placed when adding
  // Options are center,East,West,Nort and South
        add(okButton1,"Center");
          add(okButton2,"North");
          add(okButton3,"West");
          add(okButton4,"East");
          add(okButton5,"South");
        }
    }
/*<applet code="LayoutExample.java" height=200 width=300></applet>*/

java Applet example of EventListeners,ActionListener(Addition ,Subtract,Multiply,Divide)

import java.applet.*;
import java.awt.event.*;
import java.awt.*;
 
public class EventListeners extends Applet implements ActionListener{
   TextArea txtArea;
   String Add, Subtract,Multiply,Divide;
   int i = 10, j = 20, sum =0,Sub=0,Mul = 0,Div = 0;
   public void init(){
   txtArea = new TextArea(10,20);
   txtArea.setEditable(false);
   add(txtArea,"center");
   Button b = new Button("Add");
   Button c = new Button("Subtract");
   Button d = new Button("Multiply");
   Button e = new Button("Divide");
   b.addActionListener(this);
   c.addActionListener(this);
   d.addActionListener(this);
   e.addActionListener(this);
   add(b);
   add(c);
   add(d);
   add(e);
   }

   public void actionPerformed(ActionEvent e){
   sum = i + j;
   txtArea.setText("");
   txtArea.append("i = "+ i + "\t" + "j = " + j + "\n");
   Button source = (Button)e.getSource();
   if(source.getLabel() == "Add"){
   txtArea.append("Sum : " + sum + "\n");
   }
  
   if(i >j){
   Sub = i - j;
   }
   else{
   Sub = j - i;
   }
   if(source.getLabel() == "Subtract"){
   txtArea.append("Sub : " + Sub + "\n");
   }
   Mul = i*j;
   if(source.getLabel() == "Multiply"){
   txtArea.append("Mul = " + Mul + "\n");
   }
   if(i > j){
   Div = i / j;
   }
   else{
   Div = j / i;
   }
   if(source.getLabel() == "Divide"){
   txtArea.append("Divide = " + Div);
   }
   }
 }