code: public static boolean isAncestor( File ancestorCandidate, File file ) {
  
  		String path = ancestorCandidate.getAbsolutePath();
  		if( ! path.endsWith( "/" ))
  			path += "/";
  
  		return file.getAbsolutePath().startsWith( path );
  	}
docs: Determines whether a directory contains a given file.
  @param ancestorCandidate the directory
  @param file the file
  @return true if the directory directly or indirectly contains the file