From daedca9bf684b34e29b3e60a3e8ebde82045d4ae Mon Sep 17 00:00:00 2001
From: Nathan Cannon <neviynhd@gmail.com>
Date: Thu, 10 Mar 2016 16:56:05 +0000
Subject: [PATCH] Fixed hard freeze that occurred if gstreamer never started to
 actually play a song after calling the Player play method.

---
 src/main/java/musicplayer/Player.java         | 17 +++++++++------
 src/main/java/musicplayer/PlayerGUI.java      | 21 +++++++++++++------
 .../musicplayer/StartPlayingException.java    | 12 +++++++++++
 3 files changed, 38 insertions(+), 12 deletions(-)
 create mode 100644 src/main/java/musicplayer/StartPlayingException.java

diff --git a/src/main/java/musicplayer/Player.java b/src/main/java/musicplayer/Player.java
index 1570b0b..d4747ba 100644
--- a/src/main/java/musicplayer/Player.java
+++ b/src/main/java/musicplayer/Player.java
@@ -49,7 +49,7 @@ class Player {
      * Set a source Song file and start playing it via GStreamer.
      * @param inputSong Song to play.
      */
-    public void playSong(Optional<Song> inputSong){
+    public void playSong(Optional<Song> inputSong) throws StartPlayingException {
         if (playBin.getState() == State.PLAYING)
             stop();
         if(inputSong.isPresent()) {
@@ -71,11 +71,16 @@ class Player {
             thread = new Thread(internalThread, "GSTThread");
             setVolume(currentVolume);
             playBin.play();
-            thread.start();
-            while (true) {
-                if (playBin.queryDuration().getSeconds() > 0 || playBin.queryDuration().getNanoSeconds() > 0) break;
-            } // Wait for song to actually be playing otherwise queryDuration is always zero
-            callbackInterface.setSeekBarDuration((int) playBin.queryDuration().toSeconds());
+            if(playBin.getState() == State.PLAYING) {
+                thread.start();
+                while (true) {
+                    if (playBin.queryDuration().getSeconds() > 0 || playBin.queryDuration().getNanoSeconds() > 0) break;
+                } // Wait for song to actually be playing otherwise queryDuration is always zero
+                callbackInterface.setSeekBarDuration((int) playBin.queryDuration().toSeconds());
+            }
+            else{
+                throw new StartPlayingException(inputSong.get());
+            }
         }
     }
 
diff --git a/src/main/java/musicplayer/PlayerGUI.java b/src/main/java/musicplayer/PlayerGUI.java
index 1ca37cd..41fc35d 100644
--- a/src/main/java/musicplayer/PlayerGUI.java
+++ b/src/main/java/musicplayer/PlayerGUI.java
@@ -162,12 +162,21 @@ public class PlayerGUI implements PlayerCallbackInterface, LibraryCallbackInterf
         playlistTableModel.setPlayingRow(index);
     }
 
+    private void playSong(Optional<Song> song){
+        try {
+            player.playSong(song);
+        } catch (StartPlayingException e) {
+            JOptionPane.showMessageDialog(mainPanel, "Failed to play " + song.get().toString() + ".\n" +
+                    "If file path contains non-ASCII characters, please restart the application with UTF-8 encoding.");
+        }
+    }
+
     /**
      * Get the next song in the playlist and dispatch it to the Player to be played.
      */
     public void playNextSong() {
         SwingUtilities.invokeLater(() -> seekBar.setValue(0));
-        player.playSong(playlistTableModel.nextSong(player.getCurrentSong()));
+        playSong(playlistTableModel.nextSong(player.getCurrentSong()));
     }
 
     /**
@@ -175,7 +184,7 @@ public class PlayerGUI implements PlayerCallbackInterface, LibraryCallbackInterf
      */
     public void playPreviousSong() {
         SwingUtilities.invokeLater(() -> seekBar.setValue(0));
-        player.playSong(playlistTableModel.previous(player.getCurrentSong()));
+        playSong(playlistTableModel.previous(player.getCurrentSong()));
     }
 
     /**
@@ -355,9 +364,9 @@ public class PlayerGUI implements PlayerCallbackInterface, LibraryCallbackInterf
         playButton.addActionListener(e -> {
             if (playList.getRowCount() > 0) {
                 if (playList.getSelectedRowCount() > 0)
-                    player.playSong(playlistTableModel.getSong(playList.getSelectedRow()));
+                    playSong(playlistTableModel.getSong(playList.getSelectedRow()));
                 else
-                    player.playSong(playlistTableModel.getFirst());
+                    playSong(playlistTableModel.getFirst());
             }
         });
         toolBar.add(playButton);
@@ -545,9 +554,9 @@ public class PlayerGUI implements PlayerCallbackInterface, LibraryCallbackInterf
                         else{
                             if (playList.getRowCount() > 0) {
                                 if (playList.getSelectedRowCount() > 0)
-                                    player.playSong(playlistTableModel.getSong(playList.getSelectedRow()));
+                                    playSong(playlistTableModel.getSong(playList.getSelectedRow()));
                                 else
-                                    player.playSong(playlistTableModel.getFirst());
+                                    playSong(playlistTableModel.getFirst());
                             }
                         }
                         break;
diff --git a/src/main/java/musicplayer/StartPlayingException.java b/src/main/java/musicplayer/StartPlayingException.java
new file mode 100644
index 0000000..3408877
--- /dev/null
+++ b/src/main/java/musicplayer/StartPlayingException.java
@@ -0,0 +1,12 @@
+package musicplayer;
+
+import musicplayer.model.Song;
+
+public class StartPlayingException extends Exception {
+
+    private Song song;
+
+    public StartPlayingException(Song song){
+        this.song = song;
+    }
+}