Java SE (Java Platform, Standard Edition)

The "Scrollbar" not working properly, because the maximum value of the bar can not be accessed from visual part of the component. It can only be edited by their method "setValue ()."
Could you please check, thanks.
This is my example:

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Frame;
import java.awt.GridLayout;
import java.awt.Label;
import java.awt.Panel;
import java.awt.Scrollbar;
import java.awt.event.AdjustmentEvent;
import java.awt.event.AdjustmentListener;
import java.awt.event.WindowEvent;
import java.awt.event.WindowListener;

/**
*
* @author Oscar Uribe Brenes
*/
public class Ejemplo_011_Scrollbar {

static int r=0,g=0,b=0;
/**
* @param args the command line arguments
*/
public static void main(String[] args) {

Frame frame = new Frame();

Panel panel = new Panel();

final Label label = new Label();
final Label label1 = new Label();
final Label label2 = new Label();

final Label label3 = new Label();

Scrollbar scrollbar = new Scrollbar();
Scrollbar scrollbar1 = new Scrollbar();
Scrollbar scrollbar2 = new Scrollbar();

BorderLayout borderLayout = new BorderLayout();
GridLayout gridLayout = new GridLayout();

frame.setTitle("Ejemplo_011_Scrollbar");
frame.setSize(300, 100);

label.setText("Rojo: 0");
label.setAlignment(Label.RIGHT);
label.setSize(50, label.getHeight());

label1.setText("Verde: 0");
label1.setAlignment(Label.RIGHT);
label1.setSize(50, label.getHeight());

label2.setText("Azul: 0");
label2.setAlignment(Label.RIGHT);
label2.setSize(50, label.getHeight());

label3.setText("");

scrollbar.setMinimum(0);
scrollbar.setMaximum(255);
scrollbar.setValue(0);
scrollbar.setName("scrollbar");
scrollbar.setOrientation(Scrollbar.HORIZONTAL);

scrollbar1.setMinimum(0);
scrollbar1.setMaximum(255);
scrollbar1.setValue(0);
scrollbar1.setName("scrollbar1");
scrollbar1.setOrientation(Scrollbar.HORIZONTAL);

scrollbar2.setMinimum(0);
scrollbar2.setMaximum(255);
scrollbar2.setValue(0);
scrollbar2.setName("scrollbar2");
scrollbar2.setOrientation(Scrollbar.HORIZONTAL);

gridLayout.setColumns(2);
gridLayout.setRows(3);
gridLayout.setHgap(1);
gridLayout.setVgap(2);

frame.setLayout(borderLayout);
panel.setLayout(gridLayout);

WindowListener windowListener = new WindowListener() {

@Override
public void windowOpened(WindowEvent e) {
}

@Override
public void windowClosing(WindowEvent e) {

Frame frame;

if (e.getSource() instanceof Frame) {

frame = (Frame) e.getSource();
frame.dispose();

}

}

@Override
public void windowClosed(WindowEvent e) {
System.exit(0);
}

@Override
public void windowIconified(WindowEvent e) {
}

@Override
public void windowDeiconified(WindowEvent e) {
}

@Override
public void windowActivated(WindowEvent e) {
}

@Override
public void windowDeactivated(WindowEvent e) {
}
};
frame.addWindowListener(windowListener);

AdjustmentListener adjustmentListener = new AdjustmentListener() {

@Override
public void adjustmentValueChanged(AdjustmentEvent e) {

Scrollbar scrollbar;

Color color = null;

if(e.getSource()instanceof Scrollbar){
scrollbar = (Scrollbar) e.getSource();
if(scrollbar.getName().equals("scrollbar")){
r = scrollbar.getValue();
label.setText("Rojo: " + r);
}
if (scrollbar.getName().equals("scrollbar1")) {
g = scrollbar.getValue();
label1.setText("Verde: " + g);
}
if (scrollbar.getName().equals("scrollbar2")) {
b = scrollbar.getValue();
label2.setText("Azul: " + b);
}
color = new Color(r, g, b);
}
label3.setBackground(color);
}
};

scrollbar.addAdjustmentListener(adjustmentListener);
scrollbar1.addAdjustmentListener(adjustmentListener);
scrollbar2.addAdjustmentListener(adjustmentListener);

panel.add(label);
panel.add(scrollbar);
panel.add(label1);
panel.add(scrollbar1);
panel.add(label2);
panel.add(scrollbar2);

frame.add(panel, BorderLayout.CENTER);
frame.add(label3, BorderLayout.SOUTH);

frame.setLocation(200, 200);
frame.setResizable(false);
frame.setVisible(true);

}

}