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Java Local Development Environments Advanced Tooling Refactoring

Rename Refactoring code challenge: showing compilation error when answer is pasted but running error free in IDE.

I am seeing no errors in the IDE while running the KaraokeMachine.java code after performing the refactoring rename. However, it shows compilation error when I paste my answer in the challenge box.

package com.teamtreehouse;

import com.teamtreehouse.model.Song;
import com.teamtreehouse.model.SongBook;
import com.teamtreehouse.model.SongRequest;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayDeque;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Queue;

public class KaraokeMachine {

    private SongBook mSongBook;
    private BufferedReader mReader;
    private Map<String, String> mMenu;
    private Queue<SongRequest> mSongRequestQueue;

    public KaraokeMachine(SongBook songBook) {
        mSongBook = songBook;
        mReader = new BufferedReader(new InputStreamReader(System.in));
        mSongRequestQueue = new ArrayDeque<>();
        mMenu = new HashMap<String, String>();
        mMenu.put("add", "Add a new song to the song book");
        mMenu.put("play", "play the song in the queue ");
        mMenu.put("choose", "Choose a song a sing");
        mMenu.put("quit", "Give up. Exit the program");


    private String promptAction() throws IOException {
        System.out.printf("There are %d song available and %d in the queue. Your options are: %n", mSongBook.getSongCount(), mSongRequestQueue.size());
        for (Map.Entry<String, String> option : mMenu.entrySet()) {
            System.out.printf("%s - %s %n", option.getKey(), option.getValue());
        System.out.print("What do you want to do ? ");
        String choice = mReader.readLine();
        return choice.trim().toLowerCase();

    public void run() {
        String choice = "";
        do {
            try {
                choice = promptAction();
                switch (choice) {
                    case "add":

                        Song song = promptNewSong();
                        System.out.printf("%s added! %n%n", song);
                    case "choose":
                        String singerName = promptForSingerName();
                        String artist = promptArtist();
                        Song artistSong = promptSongForArtist(artist);
                        SongRequest songRequest = new SongRequest(singerName, artistSong);
                        if (mSongRequestQueue.contains(songRequest)) {
                            System.out.printf("%n%n Whoops %s alread requested %s!", singerName,

                        System.out.printf("You choose: %s %n", artistSong);
                    case "play":
                    case "quit":
                        System.out.println("Thanks for playing");
                        System.out.println("Unknown Choice");

            } catch (IOException ioe) {
                System.out.println("Problem with the input");

        } while (!choice.equals("quit"));


    private String promptForSingerName() throws IOException {
        System.out.println("Enter the singer name: ");
        return mReader.readLine();


    private Song promptNewSong() throws IOException {
        System.out.print("Enter the artist's name: ");
        String artist = mReader.readLine();
        System.out.print("Enter the title: ");
        String title = mReader.readLine();
        System.out.print("Enter the url: ");
        String url = mReader.readLine();
        return new Song(artist, title, url);

    private String promptArtist() throws IOException {
        System.out.println("Available artists");
        List<String> artists = new ArrayList<String>(mSongBook.getArtists());
        int index = promptForIndex(artists);
        return artists.get(index);

    private Song promptSongForArtist(String artists) throws IOException {
        List<Song> songs = mSongBook.getSongForArtist(artists);
        List<String> songTitle = new ArrayList<String>();
        for (Song song : songs) {
        System.out.printf("Available songs for %s; %n", artists);
        int index = promptForIndex(songTitle);
        return songs.get(index);

    private int promptForIndex(List<String> options) throws IOException {
        int counter = 1;
        for (String option : options) {
            System.out.printf("%d.)  %s  %n", counter, option);
        System.out.print("Your choice: ");
        String optionAsString = mReader.readLine();
        int choice = Integer.parseInt(optionAsString.trim());

        return choice - 1;

    public void playNext() {
        SongRequest songRequest = mSongRequestQueue.poll();
        if (songRequest == null) {
            System.out.print("Sorry there are no songRequest in the queue. Choose choose from the menu to add some");
        } else {

            Song song = songRequest.getSong();
            System.out.printf("%n%n%n Ready %s ? Open %s to hear %s by %s %n%n%n",songRequest.getSingerName(), song.getVideoUrl(), song.getTitle(), song.getArtist());


1 Answer

Ken Alger
Ken Alger
Treehouse Teacher


Take a look at line 116 in your code. I think the challenge is expecting the getSongsForArtist method but you have getSongForArtist.

Post back if you are still stuck.

Happy coding,

Yes, you are right !! Added s and it worked. Thank you so much for the quick response.