我的JScrollBar 的value 为什么总比Maximum值小10

[CanFly]

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

class Tests extends JPanel{
private JScrollBar sb;
public Tests() {
setLayout(new BorderLayout());
sb = new JScrollBar();
//sb.setMaximum(100);
//sb.setMinimum(0);

add(sb, BorderLayout.WEST);
sb.addAdjustmentListener(new AdjustmentListener() {

public void adjustmentValueChanged(AdjustmentEvent e) {
JScrollBar jsb = (JScrollBar)e.getAdjustable();

if(jsb.getValueIsAdjusting())
System.out.println("adjusting ...");
else
System.out.println(Integer.toString(e.getValue()));

}
});
}
}
class Test extends JFrame
{
public Test()
{
Container ctp=getContentPane();
ctp.setLayout(new BorderLayout());
ctp.add(new Tests(),"Center");
addWindowListener(new WindowAdapter()
{
public void windowClosing(WindowEvent e)
{
System.exit(0);
}
});
}
public static void main (String args[])
{
Test mytest=new Test();
mytest.setVisible(true);
mytest.setSize(300,300);

}
}

[masterz]

setValues
public void setValues(int newValue,
int newExtent,
int newMin,
int newMax)
Sets the four BoundedRangeModel properties after forcing the arguments to obey the usual constraints:
minimum <= value <= value+extent <= maximum

10是缺省的estent值

[masterz]

10是缺省的extent值

[CanFly]

哦 谢谢

[CanFly]

to masterz()　请教
sb.setValues(0,0,0,100);
我把extent只设成0 就可以了
extent是什么属性？

[masterz]

extent是那个滚动条(bar)代表的宽度