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Java

Posted by Ricardo Sala
Ricardo Sala
16,212 Points

ByArtist method - I don't get it!

First of all, as always, thank you in advance!

So, the thing is: this method is suppose to return a Map<String, List<Song>> with Artist (String) and Song(s) (List of Song>.

here is the code (can somebody please fix it? somehow it doesn't show correctly!):

  private Map<String, List<Song>> byArtist() {
    Map<String, List<Song>> byArtist = new HashMap<String, List<Song>>;

    for (Song song : Songs) {
      List<Song> artistSongs = byArtist.get(song.getArtist());
      if ( artistSongs = null ) {
        artistSongs = new ArrayList<>();
        byArtist.put(song.getArtist(), artistSongs); //PERO SI ESTÁ PONIENDO UN ARRAY VACÍO...
      }
      artistSongs.add(song);
    }
    return byArtist;

  }

The thing is, I DON'T SE WHEN IT SAVES THE SONGS OF THE ARTIST!

I mean, it does artistSong.add(song), but it doesn't assign that new "uploaded" list to the byArtist map!

It works, but I can't see why!

Can some moderator please comment the code so we can understand it step by step?

Thank you!

YOU ROCK!

[MOD: edited code block - srh]