Use Download class to download track previews into a Temp/ directory.

AudioSystem.getAudioInputStream(URL) was causing issues, so just download the files using the more robust Download class.

Signed-off-by: Jeffrey Han <itdelatrisu@gmail.com>

.gitignore

@@ -4,6 +4,7 @@
 /Skins/
 /SongPacks/
 /Songs/
+/Temp/
 /.opsu.log
 /.opsu.cfg
 /.opsu.db*

README.md

@@ -63,6 +63,7 @@ The following files and folders will be created by opsu! as needed:
   files within this directory to the replay directory and saves the scores in
   the scores database.  Replays can be imported from osu! as well as opsu!.
 * `Natives/`: The native libraries directory.
+* `Temp/`: The temporary files directory.  Deleted when opsu! exits.
 
 ## Building
 opsu! is distributed as both a [Maven](https://maven.apache.org/) and

src/itdelatrisu/opsu/Container.java

@@ -27,11 +27,15 @@ import itdelatrisu.opsu.downloads.Updater;
 import itdelatrisu.opsu.render.CurveRenderState;
 import itdelatrisu.opsu.ui.UI;
 
+import java.io.IOException;
+
+import org.codehaus.plexus.util.FileUtils;
 import org.lwjgl.opengl.Display;
 import org.newdawn.slick.AppGameContainer;
 import org.newdawn.slick.Game;
 import org.newdawn.slick.SlickException;
 import org.newdawn.slick.opengl.InternalTextureLoader;
+import org.newdawn.slick.util.Log;
 
 /**
  * AppGameContainer extension that sends critical errors to ErrorHandler.
@@ -142,6 +146,15 @@ public class Container extends AppGameContainer {
 		if (!Options.isWatchServiceEnabled())
 			BeatmapWatchService.destroy();
 		BeatmapWatchService.removeListeners();
+
+		// delete temporary directory
+		if (Options.TEMP_DIR.isDirectory()) {
+			try {
+				FileUtils.deleteDirectory(Options.TEMP_DIR);
+			} catch (IOException e) {
+				Log.warn(String.format("Failed to delete temp dir: %s", Options.TEMP_DIR.getAbsolutePath()), e);
+			}
+		}
 	}
 
 	@Override

src/itdelatrisu/opsu/Options.java

@@ -94,6 +94,9 @@ public class Options {
 	/** Directory where natives are unpacked. */
 	public static final File NATIVE_DIR = new File(CACHE_DIR, "Natives/");
 
+	/** Directory where temporary files are stored (deleted on exit). */
+	public static final File TEMP_DIR = new File(CACHE_DIR, "Temp/");
+
 	/** Font file name. */
 	public static final String FONT_NAME = "DroidSansFallback.ttf";
 

src/itdelatrisu/opsu/audio/SoundController.java

@@ -22,6 +22,9 @@ import itdelatrisu.opsu.ErrorHandler;
 import itdelatrisu.opsu.Options;
 import itdelatrisu.opsu.audio.HitSound.SampleSet;
 import itdelatrisu.opsu.beatmap.HitObject;
+import itdelatrisu.opsu.downloads.Download;
+import itdelatrisu.opsu.downloads.Download.DownloadListener;
+import itdelatrisu.opsu.ui.UI;
 
 import java.io.File;
 import java.io.IOException;
@@ -345,24 +348,58 @@ public class SoundController {
 	}
 
 	/**
-	 * Plays a track from a URL.
+	 * Plays a track from a remote URL.
 	 * If a track is currently playing, it will be stopped.
-	 * @param url the resource URL
+	 * @param url the remote URL
+	 * @param name the track file name
 	 * @param isMP3 true if MP3, false if WAV
 	 * @param listener the line listener
-	 * @return the MultiClip being played
+	 * @return true if playing, false otherwise
 	 * @throws SlickException if any error occurred
 	 */
-	public static synchronized MultiClip playTrack(URL url, boolean isMP3, LineListener listener) throws SlickException {
+	public static synchronized boolean playTrack(String url, String name, boolean isMP3, LineListener listener)
+		throws SlickException {
+		// stop previous track
 		stopTrack();
-		try {
-			AudioInputStream audioIn = AudioSystem.getAudioInputStream(url);
-			currentTrack = loadClip(url.getFile(), audioIn, isMP3);
-			playClip(currentTrack, Options.getMusicVolume() * Options.getMasterVolume(), listener);
-			return currentTrack;
-		} catch (Exception e) {
-			throw new SlickException(String.format("Failed to load clip '%s'.", url.getFile(), e));
+
+		// download new track
+		File dir = Options.TEMP_DIR;
+		if (!dir.isDirectory())
+			dir.mkdir();
+		String filename = String.format("%s.%s", name, isMP3 ? "mp3" : "wav");
+		final File downloadFile = new File(dir, filename);
+		boolean complete;
+		if (downloadFile.isFile()) {
+			complete = true;  // file already downloaded
+		} else {
+			Download download = new Download(url, downloadFile.getAbsolutePath());
+			download.setListener(new DownloadListener() {
+				@Override
+				public void completed() {}
+
+				@Override
+				public void error() {
+					UI.sendBarNotification("Failed to download track preview.");
+				}
+			});
+			try {
+				download.start().join();
+			} catch (InterruptedException e) {}
+			complete = (download.getStatus() == Download.Status.COMPLETE);
 		}
+
+		// play the track
+		if (complete) {
+			try {
+				AudioInputStream audioIn = AudioSystem.getAudioInputStream(downloadFile);
+				currentTrack = loadClip(filename, audioIn, isMP3);
+				playClip(currentTrack, Options.getMusicVolume() * Options.getMasterVolume(), listener);
+				return true;
+			} catch (Exception e) {
+				throw new SlickException(String.format("Failed to load clip '%s'.", url));
+			}
+		}
+		return false;
 	}
 
 	/**

src/itdelatrisu/opsu/downloads/Download.java

@@ -167,12 +167,13 @@ public class Download {
 
 	/**
 	 * Starts the download from the "waiting" status.
+	 * @return the started download thread, or {@code null} if none started
 	 */
-	public void start() {
+	public Thread start() {
 		if (status != Status.WAITING)
-			return;
+			return null;
 
-		new Thread() {
+		Thread t = new Thread() {
 			@Override
 			public void run() {
 				// open connection
@@ -274,7 +275,9 @@ public class Download {
 						listener.error();
 				}
 			}
-		}.start();
+		};
+		t.start();
+		return t;
 	}
 
 	/**

src/itdelatrisu/opsu/states/DownloadsMenu.java

@@ -47,8 +47,6 @@ import itdelatrisu.opsu.ui.UI;
 
 import java.io.File;
 import java.io.IOException;
-import java.net.MalformedURLException;
-import java.net.URL;
 
 import javax.sound.sampled.LineEvent;
 import javax.sound.sampled.LineListener;
@@ -663,15 +661,18 @@ public class DownloadsMenu extends BasicGameState {
 								SoundController.stopTrack();
 							} else {
 								// play preview
-								try {
-									final URL url = new URL(serverMenu.getSelectedItem().getPreviewURL(node.getID()));
-									MusicController.pause();
-									new Thread() {
-										@Override
-										public void run() {
-											try {
-												previewID = -1;
-												SoundController.playTrack(url, true, new LineListener() {
+								final String url = serverMenu.getSelectedItem().getPreviewURL(node.getID());
+								MusicController.pause();
+								new Thread() {
+									@Override
+									public void run() {
+										try {
+											previewID = -1;
+											boolean playing = SoundController.playTrack(
+												url,
+												Integer.toString(node.getID()),
+												true,
+													new LineListener() {
 													@Override
 													public void update(LineEvent event) {
 														if (event.getType() == LineEvent.Type.STOP) {
@@ -681,18 +682,16 @@ public class DownloadsMenu extends BasicGameState {
 															}
 														}
 													}
-												});
+												}
+											);
+											if (playing)
 												previewID = node.getID();
-											} catch (SlickException e) {
-												UI.sendBarNotification("Failed to load track preview. See log for details.");
-												Log.error(e);
-											}
+										} catch (SlickException e) {
+											UI.sendBarNotification("Failed to load track preview. See log for details.");
+											Log.error(e);
 										}
-									}.start();
-								} catch (MalformedURLException e) {
-									UI.sendBarNotification("Could not load track preview (bad URL).");
-									Log.error(e);
-								}
+									}
+								}.start();
 							}
 							return;
 						}