question: public void test_filter_001 ( ) throws IOException { final File basefile = File . createTempFile ( getName ( ) , "-test" ) ; try { final String basename = basefile . toString ( ) ; final NameAndExtensionFilter logFilter = new NameAndExtensionFilter ( basename , ".log" ) ; assertSameFiles ( new File [ ] { } , logFilter . getFiles ( ) ) ; } finally { basefile . delete ( ) ; } }
target:  Test verifies that no files are found using a guarenteed unique basename.