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Java Java Data Structures Efficiency! Menu UI

What does this line of code do?

In case : "add":

What does - mSongBook,addSong(song); do?

Craig Dennis Tonnie Fanadez Jennifer Nordell andren Simon Sporrong

1 Answer

In the run method, we are looping until the user selects "quit". If the user enters "add" as their choice we know they want to add a song to the mSongBook of the KaraokeMachine.

So we ask them for the info needed to build a Song using the promptNewSong method. This gives us a Song stored in the song variable.

Now to get the Song referenced by song into the mSongBook we use the addSong method which is an instance method of mSongBook that we wrote.

It takes the song that we created using promptNewSong as an argument which gets into the SongBook mSongs ArrayList using the built in method add.