import awb.*;
import java.awt.*;
import java.awt.event.*;

public class Numbers extends java.applet.Applet implements ActionListener
{
    TextField instruct, result, mRadius, mLength;
    DoubleField gRadius, gLength;
    Button bCompute;
    double radius, length, cylVol, pi=3.14159265;

    public void init ()
    {
	instruct = new TextField(72);
  	instruct.setText("Please enter radius and length below.");
	mRadius = new TextField(9);
  	mRadius.setText("radius:");
	mLength = new TextField(9);
  	mLength.setText("length:");
	gRadius = new DoubleField(10);
	gLength = new DoubleField(10);
	result = new TextField(72);
	result.setText("The volume of the cylinder is:  " + cylVol);
  	bCompute = new Button("Compute");
	bCompute.addActionListener(this);
  	add(instruct) ;
  	add(mRadius) ;
  	add(gRadius) ;
  	add(mLength) ;
  	add(gLength) ;
	add(bCompute) ;
  	add(result) ;
    }

    public void actionPerformed(ActionEvent event)
    {
	Object cause = event.getSource();
        if (cause == bCompute)
        {
	    length = gLength.getDouble();
	    radius = gRadius.getDouble();
            cylVol = pi * radius * radius * length;
	    result.setText("The volume of the cylinder is:  " + cylVol);
        }
    }	
}