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Java Java Data Structures Efficiency! Implement Chooser UI

Liron Tal
Liron Tal
4,825 Points
Posted by Liron Tal
Liron Tal
4,825 Points

byArtist() not working as expected

byArtist() is not working as expected, I tried 3 different songs of 2 artist, and artistSongs size was only 2. The reason is basically because we override artistSongs each iteration with byArtist.get(song.getArtist()); no matter how many times we added songs of the same artist to artistSongs..

private Map<String, List<Song>> byArtist() {
    Map<String, List<Song>> byArtist = new HashMap<>();
    for(Song song : mSongs) {
        List<Song> artistSongs = byArtist.get(song.getArtist());
        if(artistSongs == null) {
            artistSongs = new ArrayList<>();
            byArtist.put(song.getArtist(), artistSongs);
        }
        artistSongs.add(song);
    }
    return byArtist;

Debugged it and still not working as expected. Am I missing something?

Thanks, Liron