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Start your free trialSean Flanagan
33,235 PointsProblem playing a song
Hi. My song won't play.
Here's my KaraokeMachine:
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.ArrayDeque;
import java.util.ArrayList;
import java.util.Deque;
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 Queue<Song> mSongQueue;
private Map<String, String> mMenu;
public KaraokeMachine(SongBook songBook) {
mSongBook = songBook;
mReader = new BufferedReader(new InputStreamReader(System.in));
mSongQueue = new ArrayDeque<Song>();
mMenu = new HashMap<String, String>();
mMenu.put("add", "Add a new song to the song book");
mMenu.put("play", "Play the 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(),
mSongQueue.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);
mSongQueue.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 = mSongQueue.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());
}
}
}
Errors:
Enter the artist's name: The Eagles
Enter the title: Hollywood Waltz
Enter the video URL: https://www.youtube.com/watch?v=bsZCXx5WU3s
Song: Hollywood Waltz by The Eagles added!
There are 1 songs available and 0 in the queue. Your options are:
add - Add a new song to the song book
play - Play the next song in the queue
choose - Choose a song to sing!
quit - Give up. Exit the program
What do you want to do: choose
Available artists:
1.) The Eagles
Your choice: 1
Available songs for The Eagles:
1.) Hollywood Waltz
Your choice: play
Exception in thread "main" java.lang.NumberFormatException: For input string: "play"
at java.lang.NumberFormatException.forInputString(NumberFormatException.java:65)
at java.lang.Integer.parseInt(Integer.java:580)
at java.lang.Integer.parseInt(Integer.java:615)
at com.teamtreehouse.KaraokeMachine.promptForIndex(KaraokeMachine.java:118)
at com.teamtreehouse.KaraokeMachine.promptSongForArtist(KaraokeMachine.java:106)
at com.teamtreehouse.KaraokeMachine.run(KaraokeMachine.java:61)
at Karaoke.main(Karaoke.java:10)
Does anyone know why the song won't play? Cheers :-)
Snapshot: https://w.trhou.se/bapbpc88kw
1 Answer
Enrique Munguía
14,311 PointsWhen you make your choice you must enter a number because the method promptForIndex expects an integer and you are entering a string "play" and the method throws NumberFormatException as it can not parse the String to Integer
Sean Flanagan
33,235 PointsSean Flanagan
33,235 PointsHi Enrique. It looks like I entered a string instead of a number so you're right. I typed 'play' too early. When asked what I wanted to do, <i>then</i> I typed 'play'. Thanks for your help. :-)