A DESCRIPTION OF THE PROBLEM :
The DefaultTreeCellRenderer.getDefaultClosedIcon() method can return null on some platforms (see http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6299154). The documentation should mention this possibility. The same goes for getClosedIcon(), getDefaultOpenIcon() and getOpenIcon().



EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Mention that these methods can return null on some platforms.
ACTUAL -
Null return are not documented for these methods.