I noticed that your SplitDemo program sample on the Methods of the Pattern Class page returns a "unused import" message when I hover over an import statement in the NetBeans IDE edit panel.
 
RE: http://download-llnw.oracle.com/javase/tutorial/essential/regex/pattern.html
 
In fact, there are no references to java.util.regex.Matcher anywhere in this particular example, so the import statement is redundant. Otherwise, it's the only flaw (admittedly a minor one) that I've found thus far in any of the coding samples.