the "Scrollbar thicker" doesn't work, i don't what i am doing wrong in the "public void adjustmentValueChanged(AdjustmentEvent e)"

please help

thank you

Java Code:
import java.awt.*;
import java.awt.event.*;
import java.util.*;

class PaintCanvas extends Canvas implements ActionListener, AdjustmentListener
{
		Scrollbar lengthAdjuster,thicker;

		TextField lengthDisplay, thicknessDisplay,lengththicker;

		int centerX, centerY, length, length1 ,thickness = 1;

		Button   thinner, lucky, colorChange;

	PaintCanvas(Scrollbar lengthAdjuster, Scrollbar thicker, Button thinner, Button lucky,
					TextField lengthDisplay, TextField thicknessDisplay, Button colorChange,TextField lengththicker)
					{

		this.lengthAdjuster = lengthAdjuster;
		this.thicker = thicker;
		this.thinner = thinner;
		this.lucky = lucky;
		this.lengthDisplay = lengthDisplay;
		this.thicknessDisplay = thicknessDisplay;
		this.colorChange = colorChange;

		lengthAdjuster.addAdjustmentListener(this);
		//thicker.addActionListener(this);
		thicker.addAdjustmentListener(this);
		thinner.addActionListener(this);
		lucky.addActionListener(this);
		colorChange.addActionListener(this);

		setSize(200, 200);

		centerX = getWidth() / 2;
		centerY = getHeight() / 2;

		length = lengthAdjuster.getValue();
		length1 = thicker.getValue();

		lengthDisplay.setText(length+"");
		thicknessDisplay.setText(thickness+"");

		setBackground(new Color(15, 150, 200));
	}

	private void makeThicker() {
		if(thickness < 100){
		thickness += 1;
		thicknessDisplay.setText(thickness+"");
		}
		repaint();
	}

	private void makeThinner() {
		if(thickness > 0){
		thickness -= 1;
		thicknessDisplay.setText(thickness+"");
		}
		repaint();
	}

	private void makeRandomThickness() {
		Random random = new Random();
		thickness = random.nextInt(20)+1;
		thicknessDisplay.setText(thickness+"");
		repaint();
	}
	private void makeRandomColor() {
		Random rand = new Random();
       setBackground(new Color(rand.nextInt(256),
                         rand.nextInt(256),
                         rand.nextInt(256)));
	}


	public void paint(Graphics g) {
		for (int i = 0; i < thickness; i++)			// Draw 'thickness' number of adjacent lines
			g.drawLine(centerX-(length/2), centerY+i, centerX+(length/2), centerY+i);
	}

	public void actionPerformed(ActionEvent e) {

		 if (e.getSource() == thinner)
			makeThinner();
		else if (e.getSource() == lucky)
			makeRandomThickness();
		else
			makeRandomColor();

	}

	public void adjustmentValueChanged(AdjustmentEvent e) {
		length = lengthAdjuster.getValue();				// Only one scrollbar, no need for getSource() invocation
		lengthDisplay.setText(length+"");

		length1 = thicker.getValue();				// Only one scrollbar, no need for getSource() invocation


		repaint();
	}
}
Java Code:
import java.applet.*;
import java.awt.*;

public class ASimplePaintApplet extends Applet {
	public void init() {

		Scrollbar lengthAdjuster = new Scrollbar(Scrollbar.HORIZONTAL, 30, 0, 0, 100);
		TextField lengthDisplay = new TextField(3);
		lengthDisplay.setEditable(false);
		TextField thicknessDisplay = new TextField(3);
		thicknessDisplay.setEditable(false);
		//Button thicker = new Button("Thicker");

		Scrollbar thicker = new Scrollbar(Scrollbar.HORIZONTAL, 1, 0, 0, 100);
		TextField lengththicker = new TextField(3);
		lengththicker.setEditable(false);

		Button thinner = new Button("Thinner");
		Button lucky = new Button("Feeling Lucky?");
		Button colorChange = new Button("color Change");
		PaintCanvas paintCanvas = new PaintCanvas(lengthAdjuster, thicker, thinner, lucky,
									lengthDisplay, thicknessDisplay, colorChange,lengththicker);


		setLayout(new BorderLayout());

		add(paintCanvas, BorderLayout.CENTER);

		Panel buttonPanel = new Panel();
		buttonPanel.setLayout(new GridLayout(0, 1));
		buttonPanel.add(thinner);
		buttonPanel.add(thicknessDisplay);
		buttonPanel.add(thicker);
		buttonPanel.add(lengththicker);
		buttonPanel.add(lucky);
		buttonPanel.add(colorChange);

		add(buttonPanel, BorderLayout.EAST);

		Panel scrollPanel = new Panel();
		scrollPanel.add(lengthAdjuster);
		scrollPanel.add(lengthDisplay);

		add(scrollPanel, BorderLayout.SOUTH);
	}
}