protected void append_multipart(String name){
  String dot="";
  if (multipart_name.length() != 0)   dot=".";
  multipart_name=multipart_name.concat(dot + name);
}

protected void append_multipart ( String name ) { String dot = "" ; if ( multipart_name . length ( ) != 0 ) dot = "." ; multipart_name = multipart_name . concat ( dot + name ) ; }
append a new name segment to the accumulated multipart name
