code: private void addPaths(Path p) {
  
          for (String d : p.list()) {
              File dir = new File(d);
              if (dir.exists() && dir.isDirectory()) {
                  if (!includeDirectories.contains(dir))
                      includeDirectories.add(dir);
              }
          }
      }
docs: Collect all of the directories listed within enclosed path tags. Order of
  the path elements is preserved. Duplicates are included where first
  specified.
  
  @param p
  Path containing directories to include in compilation