将arraylist对象存储/跟踪到表元素

Question

Q: How do I keep track of which ArrayList element belongs to which element in a JTable for when I later have to put it all together into one single ArrayList ?

DETAILED:

I have an interface Media , and 3 classes implementing it: Book , Movie , Album . Album has an ArrayList of Songs (also a class I made, obviously).

I made a JTable as per usual with Object[][] where I can put in String s, int s and such for the time being and the user can add rows, remove rows, edit the cells, and then later I planned on going through the data and making each thing specified in the JTable and putting them into an ArrayList called ListOne of type Media so I can use ObjectOutputStream and save the List (yes, this is a demand in the assignment, I would've kept it simple personally).

But the problem is Songs are an ArrayList in the class Album , and so I made another JFrame with a JTable where one can similarly fill that one out, and then I thought I would store all of the songs the user provides into a temporary Album -object. But where do I go from here? I can't keep track of them like this if the user deletes the corresponding Album in the first JTable .

If I store these Album s in an ArrayList called ListTwo , and if the user decides to delete no.6 in ListOne , and no.6 happens to be an Album , I have to know which one to delete in ListTwo now and make sure the others' ID or key isn't affected as a result because I will need to pair them properly later. I need to know which Album 's songs in ListTwo to transfer to which of the Album s in ListOne so I can save it later.

So how would I go about keeping track of this and connecting them later?

Preliminary code:

Media interface class:

public interface Media {
    void setAuthor(String author);
    String getAuthor();
}

Book class:

public class Book implements Media {

    private String author;

    Book(){
        this.author = "";

    }

    @Override
    public void setAuthor(String author) {
        this.author = author;
    }
    @Override
    public String getAuthor() {
        return this.author;
    }

}

CD(Album) class:

import java.util.ArrayList;

public class CD implements Media {

    public class Song {
        private int seconds;
        private String songName;
        private String artist;

        Song(String name, int seconds, String artist){
            this.songName = name;
            this.seconds = seconds;
            this.artist = artist;
        }

        public String getName(){
            return this.songName;
        }
        public void setName(String name){
            this.songName = name;
        }
    }

    private ArrayList<Song> songs;

    private String artist;

    CD(){
        songs = new ArrayList<Song>();
        this.artist = "";
    }

    public void addSong(String name, int seconds, String artist){
        this.songs.add(new Song(name, seconds, artist));
    }
    public void removeSong(int position){
        this.songs.remove(position);
    }

    @Override
    public void setAuthor(String author){
        this.artist = author;
    }

    @Override
    public String getAuthor(){
        return this.artist;
    }
}

Movie class:

public class Movie implements Media {

    private String producer;

    Movie(){
        this.producer = "";
    }

    @Override
    public void setAuthor(String author){
        this.producer = author;
    }
    @Override
    public String getAuthor(){
        return this.producer;
    }
}

TABLE: http://pastebin.com/ETJGuQhD

Answer 1

My solution was to make 3 Add-buttons instead of one - one for each type of object that can be added to the final ArrayList. Then I made three separate add-functions, one for each button, and in each I not only add a row with a specific type already chosen, I also add an object of that type directly to the final ArrayList. Then I use the table.getRowSelection() as part of the createTable-function to pick out which one in the ArrayList to alter when I finish the list of Songs. After which the songs are directly stored in the Album object pointed out.

This way I can be sure that everything is in the right place, even though it is kinda clunky. But I'd rather finish on time than not finish on time.