A simple LayoutManager that lays out up to 5 widgets in a rectangle, one per border (NORTH, WEST, SOUTH, EAST, stretched along the border) and one in the middle (CENTER, stretched both ways).
Often used to combine fixed-width and/or fixed-height widgets with other that can use all available space. 

A typical application of this layout manager is to build Explorer-style GUIs, where

	* A JTree widget goes into the WEST region on the left border
	* A JToolbar widget goes into the NORTH region on the upper border
	* A JPanel with some JLabel widgets goes into the SOUTH region on the lower border as a status bar
	* Some data display (e.g. list of files) goes into the CENTER region in the middle
	* And the EAST region on the right is usually left empty

see LayoutManager''''''s, JavaSwing, SmalltalkLanguage