Modify existing JAplet...

I have the following good code from rrz@871311. This animation takes speed and radius inputs from 2 slider controls (it runs okay via netbeans, otherwise, run the HTML code after compiling the applet code).

Could you help me to remove these slider to simplify the code content. Sliders will not be used. Use the default values for these variables.

Question: Could you please remove the sliders?

Also, x to be 60 max (will require some sort of scaling to be applied showin the drum-string assembly larger and in the center of the screen).

for ref, see: https://www.experts-exchange.com/questions/27245193/Animation-help-3.html?anchorAnswerId=36347813#a36347813 

Thank you.

import javax.swing.JApplet;
import javax.swing.JButton;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JSlider;
import javax.swing.SwingUtilities;
import javax.swing.Timer;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.FlowLayout;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.text.DecimalFormat;

public class Drum extends JApplet implements ActionListener, ChangeListener {
	int drumX = 20; // location of drum left side
	int drumY = 20; // location of drum top
	int diameter = 30; // drum radius times two
	int pull = drumX + diameter; // horizontal location of bottom of rope where it being pulled
	int speed = 6; // pixels per time interval set by timer
	Animator animator; // the applet's content pane
	JSlider speedValue, dia;
	JLabel speedLabel, radiusLabel;
	JButton start, stop;
	Timer timer; // fires ActionEvent
	private void createGUI() {
		start = new JButton("Start");
		start.addActionListener(this);
		stop = new JButton("Stop");
		stop.addActionListener(this);
		JPanel contentPane = new JPanel(new BorderLayout());
		JPanel controlPanel = new JPanel(new FlowLayout());
		setContentPane(contentPane);
		animator = new Animator();
		animator.setOpaque(true);
		animator.setBackground(Color.WHITE);
		contentPane.add(animator, BorderLayout.CENTER);
		speedLabel = new JLabel("Speed");
		radiusLabel = new JLabel("Radius");
		speedValue = new JSlider(JSlider.HORIZONTAL, 1, 20, 6);
		speedValue.addChangeListener(this);
		dia = new JSlider(JSlider.HORIZONTAL, 20, 60, 40);
		dia.addChangeListener(this);
		controlPanel.add(speedLabel);
		controlPanel.add(speedValue);
		controlPanel.add(radiusLabel);
		controlPanel.add(dia);
		controlPanel.add(start);
		controlPanel.add(stop);
		contentPane.add(controlPanel, BorderLayout.NORTH);
	}
	public void init() {
		try {
			SwingUtilities.invokeAndWait(new Runnable() {
				public void run() {
					createGUI();
				}
			});
		} catch (Exception e) {
			System.err.println("createGUI didn't successfully complete:");
			e.printStackTrace();
		}
		timer = new Timer(100, this);
	}
	public void stateChanged(ChangeEvent e) {
		JSlider source = (JSlider) e.getSource();
		if (!source.getValueIsAdjusting()) {
			int value = (int) source.getValue();
			if (source == speedValue) {
				speed = value;
				animator.repaint();
			}
			if (source == dia) {
				diameter = value;
				pull = drumX + diameter;
				animator.repaint();
			}
		}
	}
	public void actionPerformed(ActionEvent e) {
		Object source = e.getSource();
		if (source == start) {
			pull = drumX + diameter;
			animator.repaint();
			timer.start();
		} else if (source == stop) {
			timer.stop();
		} else {
			pull = pull + speed;
			animator.repaint();
		}
	}
	public class Animator extends JPanel {
		DecimalFormat df = new DecimalFormat("00.00");
		Graphics2D g2d;
		double b = 0; // angle on drum where rope makes contact		
		double C = 0; // equals cos(b)
		double a = 0; // angle the drum has been rotated
		double h = 200 - drumY - diameter / 2; // height of the center of the drum from base line
		double x = pull - drumX - diameter; // distance that rope was pulled along horizontal base line
		public Animator() {
			super();
		}
		private void calculate() {
			h = 90 - drumY - diameter / 2;
			x = pull - drumX - diameter;
			double j = x / h;
			double k = (diameter/2) / h;
			C = (k * (j + k) + Math.sqrt(j * j + 2 * j * k + 1))
					/ ((j + k) * (j + k) + 1);
			b = Math.acos(C);
			a = (diameter/2 * Math.tan(b) + h/C - h) / (diameter/2) - b;
		}
		protected void paintComponent(Graphics g) {
			g2d = (Graphics2D) g;
			super.paintComponent(g2d);
			g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
			calculate();
			g2d.setColor(Color.YELLOW);
			g2d.fillOval(drumX, drumY, diameter, diameter); // drum
			g2d.setColor(Color.RED);
			//g2d.setStroke(stroke);
			g2d.drawLine(drumX + diameter/2 + (int)((diameter / 2) * Math.cos(b)), 
					     drumY + (int) diameter/2 - (int)((diameter / 2) * Math.sin(b)),
					     pull, 
					     90); // rope
			g2d.setColor(Color.BLACK);
			g2d.fillArc(drumX + 2, drumY + 2, diameter - 4, diameter - 4, -(int)(a * 57.3), 25); // drum marker
			g2d.drawString("Speed is " + (speedValue.getValue()) * 10 + " pixels/second", 30, 110);
			g2d.drawString("Radius is " + diameter/2 + " pixels", 230, 110);
			g2d.drawString("b is " + df.format(b) + " radians", 30, 125);
			g2d.drawString("a is " + df.format(a) + " radians", 250, 125);
			g2d.drawString("h is " + df.format(h), 30, 140);
			g2d.drawString("x is " + df.format(x) + " pixels", 250, 140);
			g2d.setColor(Color.CYAN);
			g2d.drawLine(5, 90, 1000, 90);
			g2d.drawLine(5, 145, 500, 145);
		}
	}
	public void stop() {
		timer.stop();
	}
}

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<html>
<head>
    <style type="text/css">
           body{ background-color:#d6eff7;}     
    </style>
<title>Drum Applet</title>
</head>
<body>
<applet code="Drum.class" width="800" height="300"></applet>
</body>
</html>

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