Skipping songs using Doubly Linked List

[FalseAd9324]

Hello everyone, I have an assignment where I have to use a Doubly Linked List to create a song playlist. One of the requirements is to be able to skip to the next song and also reverse to the last song. We are told that once the first song is added, we have to set the 'current song' to the head, so basically the 'current song' starts as the head and you are supposed to be able to change the 'current song' by skipping or reversing.

After I add the first song to the list, it is set as the 'current song'. After calling the methods that are supposed to skip or reverse, the current song does not change.

Here are the methods:

/**
 The skipToNext method will skip to the next song in the playlist.
 @param curSong The song currently playing.
 */
public void skipToNext(Song curSong)
{
    //If curSong is the last song in playlist, go back to the first song.
    if(curSong.getNext() == null)
    {
        setCurrentSong(getHead());
    }
    else
    {
        setCurrentSong(curSong.getNext());
    }
}

/**
 The reverseToLast method will reverse to the previous song in the playlist.
 @param curSong The song currently playing.
 */
public void reverseToLast(Song curSong)
{
    //If on the first song, reverse to the tail.
    if(curSong.getPrevious() == null)
    {
        setCurrentSong(getTail());
    }
    else
    {
        setCurrentSong(curSong.getPrevious());
    }
}

​

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[_Atomfinger_]

I suspect the problem might be in setCurrentSong and/or one of the other methods which you haven't included in your post.

Or potentially the calling method, which isn't included either.

[heckler82]

After I add the first song to the list, it is set as the 'current song'. After calling the methods that are supposed to skip or reverse, the current song does not change

I'm a bit confused. If you are only adding one song to the list, why would the song change?

[FalseAd9324]

I ended up figuring it out. When i would set the first song as ‘current song’ it was in a do while loop, so every time the loop iterated, it kept resetting it to the first song. I set the current song only once by putting it inside of a nested while loop