Properties p = new Properties();
p.add("KEY1","VALUE1");
p.save() //Saves in a file like Tango Properties.d but properties continue acessible
char [] key1 = p.get("KEY1");
p.load("properties.txt"); //Load the properties from the files adding the news and update de old values :D
If Tango developer like my lib i can send is not perfect but in my point of view is more usefull.