Каталоги

// Пример чтения каталога

String dirname = "/java";

File f1 = new File(dirname);

if (f1.isDirectory()) {
    System.out.println("Directory of " + dirname);
    String s[] = f1.list();
    for ( int i=0; i < s.length; i++) {
        File f = new File(dirname + "/" + s[i]);
            if (f.isDirectory()) {
                System.out.println(s[i] + " is a directory"):

            } else {
                System.out.println(s[i] + " is a file");
            }
     }
} else {
    System.out.println(dirname + " is not a directory");
}