A PlayList project will be based on Three Classes

• Artist
• Song
• PlayList

The Artist class will store core information about an artist

The Song class will store basic information about a music song

The PlayList class will manage lists of songs and artists

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Artist

• Constructor(s) :
  public Artist( String name) { //missing code }

 

• Instance Variables (“global” variables)
  

 

Methods

 

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Song

Constructor(s):

Instance Variables

example of how to get current milliseconds as a long

Method

 

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Artist

Song

PlayList

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PlayList

• Instance Variables
  • private String listName : This is the ‘name’ of your playList
  • private Song[] songs;
  • private  int[] stars ; //how many stars each song has between 0 and 5 inclusive.
  • Note: songs and stars are parallel Arrays
• Constructor
  • public PlayList(String name) : There should be only 1 constructor that takes a parameter representing the name of the playList
• Accessor Methods
  • public double averageRating() // returns the average star rating for the list
  • public double averageRating(Artist artist)  // returns the mean star rating associated with artist
  • public Song[] getSongs(Artist artist) // returns an array populated by the songs of the parameter artist
  • public Song[] getSongs() // returns all the songs in the list

  Mutator Methods

  • public void swap(Song song1 ,  Song song2 )  // switches positions of these two (maintain parallelism!)
  • public void  add(Song song , int stars)
  • public void removeSong(Song song, String artist )  //removes song associated with artist
    • Note: Be careful here. You are allowed to add the same song and artist. Duplicates are allowed.
  • public void removeArtist(Artist artist ) //removes all elements associated with artist
  • public void removeLowStars(int cutOff) //removes all elements associated with a star rating less than cutOff
  •  ** public PlayList sortByDate() //this returns a rearranged PlayList based on each Song’s date
  • ** public PlayList sortByRating() //this returns a rearranged playlist so that the 5 starred elements are the first group in the list, 4 stars second …1 stars, last
  • ** public PlayList shuffle() //this returns a new PlayList in which all of the songs have been reordered randomly.

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Artist

Song

PlayList