/**
  * Don't show expansion button on leaves leaf: all children are (file) or (directory named "." or
  * "..")
  *
  * @param node
  * @return whether node is a leaf
  */
 private static boolean isLeafDirectory(DirectoryNode node) {
   Directory dir = node.getLookup().lookup(Directory.class);
   boolean ret = true;
   try {
     for (Content c : dir.getChildren()) {
       if (c instanceof Directory
           && (!((Directory) c).getName().equals(".")
               && !((Directory) c).getName().equals(".."))) {
         ret = false;
         break;
       }
     }
   } catch (TskException ex) {
     Logger.getLogger(DirectoryTreeFilterChildren.class.getName())
         .log(Level.WARNING, "Error getting directory children", ex);
     return false;
   }
   return ret;
 }
 /** Helper to ignore the '.' and '..' directories */
 private static boolean isDotDirectory(DirectoryNode dir) {
   String name = dir.getDisplayName();
   return name.equals(DirectoryNode.DOTDIR) || name.equals(DirectoryNode.DOTDOTDIR);
 }