Graphical User Interfaces - JavaTech: An Introduction to Scientific and Technical Computing with Java - page 225

/** A simple example of a Panel with five buttons. **/
class FlowPanel extends JPanel
{
FlowPanel () {
// Default for JPanel is FlowLayout
add (new JButton ("One"));
add (new JButton ("Two"));
add (new JButton ("Three"));
add (new JButton ("Four"));
add (new JButton ("Five"));
} // ctor
} // class FlowPanel
The FlowPanel is a subclass of JPanel ,which uses FlowLayout as its
default layout. Each component added to the panel will be inserted from left to
right until there is no room and then the components will go to the next row
down and continue left to right. By default, FlowLayout attempts to center
the group of components. Left- or right-alignment can be specified with one
of the overloaded constructors or with the setAlignment() method and the
constants FlowLayout.LEFT or FlowLayout.RIGHT .
7.4.2 BoxLayout and Box
FlowLayout arranges components horizontally until it runs out of space and
then shifts down vertically to the next row. Before Swing, there was no good way
to arrange components in a vertical manner. The javax.swing.BoxLayout
solved that omission. BoxLayout arranges components sequentially like the
FlowLayout manager but it will set them either horizontally or vertically as
instructed. Unlike FlowLayout ,however, it will not continue the components
on the next line or column when there is insufficient room. Components out of
range will not be shown. The following code produces the arrangement shown
in Figure 7.9(a):
public class BoxLayoutApplet extends JApplet
{
. ..init() builds the interface ...
} // class BoxLayoutApplet
/** Arrange components with a BoxLayout manager. **/
class BoxPanel extends JPanel