Welcome to the Treehouse Community
Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.
Looking to learn something new?
Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.
Start your free trialMahyar Najizad
5,863 PointsHi I did what was asked and I keep receiving this error
Hi I did what was asked and I keep receiving this error what should I do ?
package com.teamtreehouse;
import com.teamtreehouse.model.Song;
import com.teamtreehouse.model.SongBook;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.*;
public class KaraokeMachine {
private SongBook mSongBook;
private BufferedReader mReader;
private Queue<Song> mSongRequestQueue;
private Map<String, String> mMenu;
public KaraokeMachine(SongBook songBook) {
mSongBook = songBook;
mReader = new BufferedReader(new InputStreamReader(System.in));
mSongRequestQueue = new ArrayDeque<Song>();
mMenu = new HashMap<String, String>();
mMenu.put("add", "Add a new song to the song book");
mMenu.put("play", "Play next song in the queue");
mMenu.put("choose", "Choose a song to sing!");
mMenu.put("quit", "Give up. Exit the program");
}
private String promptAction() throws IOException {
System.out.printf("There are %d songs 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();
mSongBook.addSong(song);
System.out.printf("%s added! %n%n", song);
break;
case "choose":
String artist = promptArtist();
Song artistSong = promptSongForArtist(artist);
mSongRequestQueue.add(artistSong);
System.out.printf("You chose: %s %n", artistSong);
break;
case "play":
playNext();
break;
case "quit":
System.out.println("Thanks for playing!");
break;
default:
System.out.printf("Unknown choice: '%s'. Try again. %n%n%n",
choice);
}
} catch (IOException ioe) {
System.out.println("Problem with input");
ioe.printStackTrace();
}
} while (!choice.equals("quit"));
}
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 video URL: ");
String videoUrl = mReader.readLine();
return new Song(artist, title, videoUrl);
}
private String promptArtist() throws IOException {
System.out.println("Available artists:");
List<String> artists = new ArrayList<>(mSongBook.getArtists());
int index = promptForIndex(artists);
return artists.get(index);
}
private Song promptSongForArtist(String artist) throws IOException {
List<Song> songs = mSongBook.getSongsForArtist(artist);
List<String> songTitles = new ArrayList<>();
for (Song song : songs) {
songTitles.add(song.getTitle());
}
System.out.printf("Available songs for %s: %n", artist);
int index = promptForIndex(songTitles);
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);
counter++;
}
System.out.print("Your choice: ");
String optionAsString = mReader.readLine();
int choice = Integer.parseInt(optionAsString.trim());
return choice - 1;
}
public void playNext() {
Song song = mSongRequestQueue.poll();
if (song == null) {
System.out.println("Sorry there are no songs in the queue." +
" Use choose from the menu to add some");
} else {
System.out.printf("%n%n%n Open %s to hear %s by %s %n%n%n",
song.getVideoUrl(),
song.getTitle(),
song.getArtist());
}
}
}
2 Answers
Anastasia Serebryakova
6,462 PointsHi! Its seems that you missed some changes that was made in a video "Refactoring". For example, mSongRequestQueue - should be a queue of SongRequests.
So instead of: private Queue<Song> mSongRequestQueue;
you should have: private Queue<SongRequest> mSongRequestQueue;
Mahyar Najizad
5,863 Pointsthanks. You solved my problem.