Storing arrays (hashmaps)

Is it possible to store arrays (hashmaps) so you can later reload them? If yes, could you attach a snippet, please?

Thanks!

 

I would like to know too, I think you'd use some kind of database. Perhaps putting them into a .yml file. Anyways, I like your signature.

 

Haha, thanks, I think it might be quite hard for people to get the second one, though. Are you also in this kind of music?

And yes, I think it should be that way, yml files..

 

Something like this should work:

Code:

BufferedWriter writer = null;

try
{
    writer = new BufferedWriter(new FileWriter("file.txt"));
    
    for (Object key: hashMap.keySet())
    {
        writer.write(key + ":" + hashMap.get(key));
        writer.newLine();
    }

    writer.close();
}
catch (Exception e) {}

It'll write each entry in the HashMap to a line in file.txt. You can then read the file and load them back into a HashMap.

 

That'll be fine if your hash-map is full of numbers and strings but if it's full of players and itemStacks or something you might have some trouble reading them back in again...

 

Alright, and how about achieving them back into your hashmap?

 

Depends what you're trying to get. This is just an example of one type of hashmap :

Code:

        Scanner in = new Scanner(new File("file.txt"));
        HashMap<Integer, Double> map = new HashMap<Integer, Double>();

        while(in.hasNextLine()){

            String line = in.nextLine();
            if(line != null){

                try {

                    map.put(Integer.parseInt(line.split(":")[0]), Double.parseDouble(line.split(":")[1]));

                } catch(Exception e){
                    System.out.println("Error reading save file.");
                }

            }

        }

 

Ah, that's actually very simple! Thanks for sharing this! And about Player hashmaps, you can also store just the playername if that's possible in the relevant plugin.

 

HashMaps are serializable. Use ObjectOutputStream to write them to file, and then ObjectInputStream to read them (don't forget to cast from Object to HashMap).

 

Saving a Object like a Player to a File would make that file huge no?