Coding

Java is similar to C in some respects but it philosophy is much closer to Object Pascal. The following code is all that is requried to produce the hello applet embedded in this page.

import java.applet.*;
import java.awt.*;

public class Hello extends Applet
{
        private Button clearBtn;
        private Button drawBtn;
        private String drawStr="";

        public Hello(){}  // the constructor for the class

        public void init()
        {// called to initialize the applet
                this.setBackground(Color.white);
                clearBtn= new Button("Clear");
                this.add(clearBtn);
                drawBtn= new Button("Draw");
                this.add(drawBtn);
        }

        public boolean action(Event evt, Object arg)
        {// handle the button clicks
                if(evt.target==clearBtn)
                {
                        drawStr="";
                        repaint();
                        return true;
                } 
                else if (evt.target==drawBtn)
                {
                        drawStr="Hello World";
                        repaint();
                        return true;
                }
                else  return super.action(evt,arg);
        }

        public void destroy(){}

        public void paint(Graphics g)
        {// paint the string
            Rectangle r=this.bounds();
                g.drawString(drawStr, r.width/2, r.height/2);
        }

        public void start(){}
        
        public void stop(){}
}