Bug 45108

May be too late for D. Should be considered a priority for E, however.

An additional possible utility method would be to take a folder and
scan for likely package roots inside of it. However I am not sure any
of our existing wizards would use such a method.

Package root verification would apply to j2seproject import; freeform
project creation and customization; possibly to web app import, TBD.

*** Issue 61234 has been marked as a duplicate of this issue. ***

Please, reevaluate. Will this be done for F?

Easy to do, it can be done to 4.2 as a fix

Something like this:

String WHITESPACE = "(?:\\s|/\\*(?:[^*]|\\*[^/])*\\*/)";
String IDENTIFIER = "(?:\\p{javaJavaIdentifierStart}\\p{javaJavaIdentifierPart}*)";
String QUALIFIED_IDENTIFIER = "(?:" + IDENTIFIER + "(?:\\." + IDENTIFIER + ")*)";
Pattern PACKAGE = Pattern.compile(
    "^" + WHITESPACE + "*(?:package" + WHITESPACE + "+(" + QUALIFIED_IDENTIFIER +
    ")|(?:import|public|final|abstract|strictfp|class|interface|enum))",
Pattern.DOTALL);
FileObject findRoot(FileObject file) {
  if (file.isFolder()) {
    // could also scan for contained files here
    return null;
  }
  // look for package statement
  try {
    InputStream is = file.getInputStream();
    try {
      ByteArrayOutputStream baos = new ByteArrayOutputStream((int) file.getSize());
      FileUtil.copy(is, baos);
      String content = baos.toString(); // XXX default encoding OK?
      Matcher m = PACKAGE.matcher(content);
      if (m.find()) {
        String pkg = m.group(1);
        FileObject root = file.getParent();
        List<String> components = new ArrayList<String>();
        if (pkg != null) {
          StringTokenizer tok = new StringTokenizer(pkg, ".");
          while (tok.hasMoreTokens()) {
            components.add(tok.nextToken());
          }
          Collections.reverse(components);
        }
        for (String component : components) {
          if (root == null || !root.getNameExt().equals(component)) {
            return null;
          }
          root = root.getParent();
        }
        return root;
      }
    } finally {
      is.close();
    }
  } catch (IOException x) {
    Exceptions.printStackTrace(x);
  }
  return null;
}