序列化列表<list<string> &gt; 无限循环迭代器.hasNext() JAVA </list<string>

Question

I've been trying to serialize a List<List< String >> in Java but my code gets stucks in a loop. Here's the code:

 public void Serializing(List<List<String>> player,File file ) throws IOException{
        
        try {
            fileOut=new FileOutputStream(file);
            out= new ObjectOutputStream(fileOut);
            Iterator <List <String>> it=player.listIterator();
          while(it.hasNext()){ //Somehow if i don't put this just adds my first element 
              out.writeObject(player.listIterator().next());
            }
            fileOut.close();
            out.close();
            
        } catch (FileNotFoundException ex) {
            Logger.getLogger(ManejoInformacion.class.getName()).log(Level.SEVERE, null, ex);
        }
    }

I'm adding the deserializable method just in case

public  List<List<String>> deserializable(File file) throws FileNotFoundException, IOException, ClassNotFoundException{
        ObjectInputStream in;
        List<List<String>> info;
        try (FileInputStream fileIn = new FileInputStream(file)) {
            in =new ObjectInputStream(fileIn);
            info = new ArrayList<>();
            info =(List<List<String>>)in.readObject();
         }      in.close();
        return info;
    }

Hope this is enough: Thank you :)

Answer 1

Here:

out.writeObject(player.listIterator().next());

you're creating a new iterator. But you already had an iterator, and you need to use that one so its state is updated.

out.writeObject(it.next());

Otherwise it.hasNext() stays true because you're not taking items from it .

Alternatively, get rid of all reference to iterators, get rid of the while-loop, and just use a for-loop:

for (List<String> item: player) {
    out.writeObject(item);
}

The for-loop handles the iterator implicitly, so you don't have to.