The code below prints all the directories and files under supplied directory name. It further provides a filter class.

Java Code:
    private static void doFileFilterListing(String dirName, String ff) {

        System.out.println("Filter file listing...");
        System.out.println("----------------------");

        final String fileFilter = ff;

        File           dir     = new File(dirName);
        FilenameFilter filter  = null;

        if (fileFilter != null) {

            // It is also possible to filter the list of returned files.
            // This example uses the passed in String value (if any) to only
            // list those files that start with the given String.
            filter = new FilenameFilter() {
                public boolean accept(File dir, String name) {
                    return name.startsWith(fileFilter);
                }
            };
        }
        String[] children = dir.list(filter);

        printFiles(children, dirName);

    }