Added seek bar that auto updates with music play duration. Currently no click seek support.

src/main/java/musicplayer/Player.java

@@ -26,7 +26,7 @@ public class Player {
         playBin.connect((PlayBin2.ABOUT_TO_FINISH) playBin2 -> {
             Thread callbackThing = new Thread(() -> {
                 try {
-                    Thread.sleep(1500); // Song is about to finish, wait so we don't cut it off early.
+                    Thread.sleep(1000); // Song is about to finish, wait so we don't cut it off early.
                 } catch (InterruptedException e) {
                     e.printStackTrace();
                 }
@@ -42,18 +42,22 @@ public class Player {
         File songFile = song.getSongFile();
         if (playBin.getState() == State.PLAYING)
             stop();
+        playBin.setState(State.READY);
         playBin.setURI(songFile.toURI());
         internalThread = new InternalThread();
         thread = new Thread(internalThread);
         playBin.play();
         thread.start();
+        while(true){
+            if (playBin.isPlaying()) break;
+        } // Wait for song to actually be playing otherwise queryDuration is always zero
+        callbackInterface.setSeekBarDuration((int) playBin.queryDuration().toSeconds());
     }
 
     public void stop() {
         if (this.thread != null) {
             playBin.stop();
             internalThread.stop();
-            thread.interrupt();
             thread = null;
         }
     }
@@ -70,6 +74,10 @@ public class Player {
         return currentSong;
     }
 
+    public int currentSongPosition(){
+        return playBin.isPlaying() ? (int) (playBin.getClock().getTime().toSeconds() - playBin.getBaseTime().toSeconds()) : 0;
+    }
+
     private class InternalThread implements Runnable {
 
         @Override

src/main/java/musicplayer/PlayerCallbackInterface.java

@@ -7,4 +7,7 @@ public interface PlayerCallbackInterface {
     Song getNextSong(Song currentSong);
 
     void setSongHighlighting(Song playingSong);
+
+    void setSeekBarDuration(int seconds);
+
 }

src/main/java/musicplayer/PlayerGUI.form

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <form xmlns="http://www.intellij.com/uidesigner/form/" version="1" bind-to-class="musicplayer.PlayerGUI">
-  <grid id="27dc6" binding="mainPanel" layout-manager="GridLayoutManager" row-count="2" column-count="2" same-size-horizontally="false" same-size-vertically="false" hgap="-1" vgap="-1">
+  <grid id="27dc6" binding="mainPanel" layout-manager="GridLayoutManager" row-count="3" column-count="2" same-size-horizontally="false" same-size-vertically="false" hgap="-1" vgap="-1">
     <margin top="0" left="0" bottom="0" right="0"/>
     <constraints>
       <xy x="20" y="20" width="500" height="400"/>
@@ -10,7 +10,7 @@
     <children>
       <scrollpane id="2b209">
         <constraints>
-          <grid row="0" column="0" row-span="2" col-span="1" vsize-policy="7" hsize-policy="7" anchor="0" fill="3" indent="0" use-parent-layout="false"/>
+          <grid row="0" column="0" row-span="3" col-span="1" vsize-policy="7" hsize-policy="7" anchor="0" fill="3" indent="0" use-parent-layout="false"/>
         </constraints>
         <properties/>
         <border type="none"/>
@@ -38,7 +38,7 @@
       </scrollpane>
       <toolbar id="56df">
         <constraints>
-          <grid row="1" column="1" row-span="1" col-span="1" vsize-policy="0" hsize-policy="6" anchor="0" fill="1" indent="0" use-parent-layout="false">
+          <grid row="2" column="1" row-span="1" col-span="1" vsize-policy="0" hsize-policy="6" anchor="0" fill="1" indent="0" use-parent-layout="false">
             <preferred-size width="-1" height="20"/>
           </grid>
         </constraints>
@@ -67,6 +67,19 @@
           </component>
         </children>
       </toolbar>
+      <component id="98c55" class="javax.swing.JSlider" binding="seekBar">
+        <constraints>
+          <grid row="1" column="1" row-span="1" col-span="1" vsize-policy="0" hsize-policy="6" anchor="8" fill="1" indent="0" use-parent-layout="false"/>
+        </constraints>
+        <properties>
+          <inverted value="false"/>
+          <minorTickSpacing value="1"/>
+          <paintTicks value="false"/>
+          <snapToTicks value="false"/>
+          <value value="0"/>
+          <valueIsAdjusting value="false"/>
+        </properties>
+      </component>
     </children>
   </grid>
 </form>

src/main/java/musicplayer/PlayerGUI.java

@@ -19,6 +19,7 @@ public class PlayerGUI implements PlayerCallbackInterface{
     private JButton playButton;
     private JButton stopButton;
     private JButton nextButton;
+    private JSlider seekBar;
     private Player player = new Player(this);
     private PlaylistTableModel playlistTableModel = new PlaylistTableModel(new ArrayList<>());
 
@@ -50,6 +51,23 @@ public class PlayerGUI implements PlayerCallbackInterface{
         });
         stopButton.addActionListener(e -> player.stop());
         nextButton.addActionListener(e -> playNextSong());
+
+        Thread seekBarUpdater = new Thread(() -> {
+            boolean running = true;
+            while (running) {
+                try {
+                    Thread.sleep(1000);
+                    setSeekBarPosition(player.currentSongPosition());
+                } catch (InterruptedException e) {
+                    running = false;
+                }
+            }
+        });
+        seekBarUpdater.start();
+    }
+
+    public void setSeekBarPosition(int position){
+        SwingUtilities.invokeLater(() -> seekBar.setValue(position));
     }
 
     private void resetTree() {
@@ -101,9 +119,14 @@ public class PlayerGUI implements PlayerCallbackInterface{
     }
 
     public void playNextSong(){
+        SwingUtilities.invokeLater(() -> seekBar.setValue(0));
         player.playSong(getNextSong(player.getCurrentSong()));
     }
 
+    public void setSeekBarDuration(int seconds){
+        SwingUtilities.invokeLater(() -> seekBar.setMaximum(seconds));
+    }
+
     private class libraryMouseAdapter extends MouseAdapter {
         @Override
         public void mousePressed(MouseEvent e) {

src/main/java/musicplayer/PlaylistTableModel.java

@@ -70,6 +70,12 @@ public class PlaylistTableModel extends AbstractTableModel {
         return songList.get(index);
     }
 
+    public Song previous(Song song){
+        int index = songList.indexOf(song) - 1;
+        if(index < 0) index = songList.size() - 1;
+        return songList.get(index);
+    }
+
     public int getSongIndex(Song song){
         return songList.indexOf(song);
     }