Displaying an applet in HTML

Question

hello ... iam having problem writing java applet and link it with html file

java applet is about drawing a pie chart 3 values sales, membership and adds. the code for java applet :

import java.awt.*;
import javax.swing.*;
import javax.swing.border.*;

/**
 * Class AppDemo - write a description of the class here
 *
 * @author (your name)
 * @version (a version number)
 */
public class AppDemo extends JApplet
{
    public void init()
    {
        Container appC = getContentPane();

        MyPanel myp = new MyPanel() ;
        myp.setBorder(new EtchedBorder() ) ;
        myp.setBackground(Color.red);
        appC.add(myp);
    }
}


class MyPanel extends JPanel {
    public void paint(Graphics g)
    {
        g.setFont(  new Font("Verdana", Font.BOLD , 18) ) ;
        g.setColor(Color.green);
        g.drawString("HELLO WORLD", 20, 20);
        g.fillArc( 20, 50, 200, 200 , 0 , 90 ) ;
        g.setColor(  new Color(255, 128, 64) ) ;
        g.fillArc( 20, 50, 200, 200 , 90 , 40 ) ;
        g.setColor(  Color.pink ) ;
        g.fillArc( 20, 50, 200, 200 , 130 , 230 ) ;
    }
}

now i want o take out the first slice.. add the following to the first parameter only (the x coordinate) of the fillArc method

(int) Math.round(Math.cos(put_first_value_here/360.0*Math.PI)*20)

add the following to the second parameter only (the y coordinate) of the fillArc method

-((int) Math.round(Math.sin(put_first_value_here/360.0*Math.PI)*20))

where first_value is the angle of the first arc

and the html file :

<APPLET CODE="AppDemo.class" CODEBASE="." WIDTH=500 HEIGHT=500>
<param name=adds value=1100 />
<param name=memberships value=300/>
<param name=sales value=1000/>
</APPLET>

end of html file

they told me to use constructor to get the values but i don't know how to do it and i didn't understand why i should use it

thanks in advance

Answer 1

Google for a tutorial .. e.g. http://www.dgp.toronto.edu/~mjmcguff/learn/java/

read, understand, adapt, test => hand in homework ..

Answer 2

If I understand correctly, you wish to access the values contained in the <param.../> tags from within your applet. An applet may access these parameters via the getParameter(String) method. You typically access these values within the init() method:

public class AppDemo extends JApplet
{
    public void init()
    {
        String adds = getParameter("adds");
        String memberships = getParameter("memberships");
        String sales = getParameter("sales");

        // The rest of your init() code...
    }
}