Solved Save/Load strings to/from file?

Alright. I had a long pause in plugin development...
Trying to figure out how I can handle this stuff for a working file-based friendlist-system.
Already wrote a plugin with a SQL-based friendlist but that's not what I need now.

I got:
- Playername (string)
- Newfriend (string)
- 2 commands (add and remove)

Code:java

 
if(command.getName().equalsIgnoreCase("add") && (args.length == 1)) {
           String playername = player.getName();
           String newfriend = args[0].toLowerCase();
 
// Check if "newfriend" exist on the friendlist of "playername".
// If exist -> sendmessage
// Else -> add "newfriend"
// Save that stuff to a file (immediately)
}
 

I want to save that stuff immediately to the friendlist file (one file for everything would be nice).
Example:

Code:

recon;friend1,friend2,friend3
peter;friend1,friend2

How can I turn that into a working command?

 

Something like this might work:

Code:

if(this.getConfig().contains(playername + ".Friends"))
{
    List<String> friends = this.getConfig().getStringList(playername + ".Friends")
    if(friends.contains(newfriend)
    {
        //send Message
    }
    else
    {
        friends.add(newfriend);
        this.getConfig().set(playername  + ".Friends", friends);
        this.saveConfig();
    }
}
else
{
    String[] friends = {newfriend};
    this.getConfig().set(playername  + ".Friends", Arrays.asList(friends));
    this.saveConfig();
}

 

Wow... I didn't thought about using the yaml config *facepalm*.
I was about to use the BufferedWriter of Java itself and stuff like that.
Thanks for rescuing me =)