Question

I have a HashMap in the following format.

HashMap<String, List<String>> map

I’m trying without any luck to find the best way to write this out to a property file, is this possible? I had no problem with a HashMap<String, String> hashmap, but when the value is a List I can’t figure out the best way to store this out. I Don’t care if it’s out in xml format or any other format, just so I can easily open the file and have it serialized or whatever back into a hashmap.

Thanks for any direction

Answer 1

A HashMap is Serializable; so you can do this by default.

FileOutputStream fileStream = new FileOutputStream("map.map");
ObjectOutputStream os = new ObjectOutputStream(fileStream);
os.writeObject(map);
os.close();