12.3 GridLayout
A GridLayout allows you to build a table of components, and as you
add them they are placed left-to-right and top-to-bottom in the grid. In
the constructor you specify the number of rows and columns that you need
and these are laid out in equal proportions.
Case Study: GridLayout1.java
In this case there are 21 slots but only 20 buttons. The last slot
is left empty; no "balancing" goes on with a GridLayout.