Reworked UI to have horizontal scalability between library and playlist.

src/main/java/musicplayer/Player.java

@@ -17,6 +17,10 @@ public class Player {
     private Song currentSong;
     private PlayerCallbackInterface callbackInterface;
 
+    /**
+     * Manages GStreamer based playback operations.
+     * @param callbackInterface Interface on which UI updates can be called.
+     */
     public Player(PlayerCallbackInterface callbackInterface) {
         this.callbackInterface = callbackInterface;
         Gst.init();
@@ -36,6 +40,10 @@ public class Player {
         });
     }
 
+    /**
+     * Set a source Song file and start playing it via GStreamer.
+     * @param song Song to play.
+     */
     public void playSong(Song song) {
         callbackInterface.setSongHighlighting(song);
         currentSong = song;
@@ -54,6 +62,9 @@ public class Player {
         callbackInterface.setSeekBarDuration((int) playBin.queryDuration().toSeconds());
     }
 
+    /**
+     * Stop any music currently playing.
+     */
     public void stop() {
         if (this.thread != null) {
             playBin.stop();
@@ -62,18 +73,30 @@ public class Player {
         }
     }
 
+    /**
+     * Resume playing a paused song.
+     */
     public void resume() {
         playBin.play();
     }
 
+    /**
+     * Pause the currently playing song.
+     */
     public void pause() {
         playBin.pause();
     }
 
+    /**
+     * @return The Song currently being played or ready to be played.
+     */
     public Song getCurrentSong(){
         return currentSong;
     }
 
+    /**
+     * @return Current playback position in seconds.
+     */
     public int currentSongPosition(){
         return playBin.isPlaying() ? (int) (playBin.getClock().getTime().toSeconds() - playBin.getBaseTime().toSeconds()) : 0;
     }

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="3" 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="1" 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"/>
@@ -8,37 +8,63 @@
     <properties/>
     <border type="none"/>
     <children>
-      <scrollpane id="2b209">
+      <splitpane id="79ccb">
         <constraints>
-          <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"/>
+          <grid row="0" column="0" row-span="1" col-span="1" vsize-policy="3" hsize-policy="3" anchor="0" fill="3" indent="0" use-parent-layout="false">
+            <preferred-size width="760" height="500"/>
+          </grid>
         </constraints>
-        <properties/>
+        <properties>
+          <dividerLocation value="350"/>
+        </properties>
         <border type="none"/>
         <children>
-          <component id="6b9fd" class="javax.swing.JTree" binding="libraryView">
+          <scrollpane id="2b209">
-            <constraints/>
+            <constraints>
+              <splitpane position="left"/>
+            </constraints>
             <properties/>
-          </component>
+            <border type="none"/>
+            <children>
+              <component id="6b9fd" class="javax.swing.JTree" binding="libraryView">
+                <constraints/>
+                <properties/>
+              </component>
+            </children>
+          </scrollpane>
+          <scrollpane id="359a1">
+            <constraints>
+              <splitpane position="right"/>
+            </constraints>
+            <properties/>
+            <border type="none"/>
+            <children>
+              <component id="c10f" class="javax.swing.JTable" binding="playList">
+                <constraints/>
+                <properties>
+                  <rowSelectionAllowed value="true"/>
+                </properties>
+              </component>
+            </children>
+          </scrollpane>
         </children>
-      </scrollpane>
+      </splitpane>
-      <scrollpane id="359a1">
+      <component id="98c55" class="javax.swing.JSlider" binding="seekBar">
         <constraints>
-          <grid row="0" column="1" row-span="1" col-span="1" vsize-policy="7" hsize-policy="7" anchor="0" fill="3" indent="0" use-parent-layout="false"/>
+          <grid row="1" column="0" row-span="1" col-span="1" vsize-policy="0" hsize-policy="6" anchor="8" fill="1" indent="0" use-parent-layout="false"/>
         </constraints>
-        <properties/>
+        <properties>
-        <border type="none"/>
+          <inverted value="false"/>
-        <children>
+          <minorTickSpacing value="1"/>
-          <component id="c10f" class="javax.swing.JTable" binding="playList">
+          <paintTicks value="false"/>
-            <constraints/>
+          <snapToTicks value="false"/>
-            <properties>
+          <value value="0"/>
-              <rowSelectionAllowed value="true"/>
+          <valueIsAdjusting value="false"/>
-            </properties>
+        </properties>
-          </component>
+      </component>
-        </children>
-      </scrollpane>
       <toolbar id="56df">
         <constraints>
-          <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">
+          <grid row="2" column="0" 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>
@@ -67,19 +93,6 @@
           </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

@@ -66,10 +66,17 @@ public class PlayerGUI implements PlayerCallbackInterface{
         seekBarUpdater.start();
     }
 
+    /**
+     * Set the value of seekBar.
+     * @param position New seekBar value.
+     */
     public void setSeekBarPosition(int position){
         SwingUtilities.invokeLater(() -> seekBar.setValue(position));
     }
 
+    /**
+     * Reset the libraryView to contain nothing.
+     */
     private void resetTree() {
         libraryView.removeAll();
         DefaultMutableTreeNode rootNode = new DefaultMutableTreeNode();
@@ -77,6 +84,10 @@ public class PlayerGUI implements PlayerCallbackInterface{
         libraryView.setModel(treeModel);
     }
 
+    /**
+     * Populate the library with songs grouped by album.
+     * @param libraryData Map of albums with a lists of associated songs.
+     */
     private void populateLibrary(Map<Album, List<Song>> libraryData) {
         resetTree();
         DefaultMutableTreeNode parentNode = (DefaultMutableTreeNode) libraryView.getModel().getRoot();
@@ -87,6 +98,10 @@ public class PlayerGUI implements PlayerCallbackInterface{
         });
     }
 
+    /**
+     * Populate the library with all songs.
+     * @param libraryData List of songs.
+     */
     private void populateLibrary(List<Song> libraryData) {
         resetTree();
         DefaultMutableTreeNode parentNode = (DefaultMutableTreeNode) libraryView.getModel().getRoot();
@@ -94,6 +109,11 @@ public class PlayerGUI implements PlayerCallbackInterface{
 
     }
 
+    /**
+     * Add an item to libraryView.
+     * @param parentNode Node that should be the parent of this node.
+     * @param node This node.
+     */
     private void addNodeToTreeModel(DefaultMutableTreeNode parentNode, DefaultMutableTreeNode node) {
         DefaultTreeModel libraryModel = (DefaultTreeModel) libraryView.getModel();
         libraryModel.insertNodeInto(node, parentNode, parentNode.getChildCount());
@@ -102,27 +122,47 @@ public class PlayerGUI implements PlayerCallbackInterface{
         }
     }
 
+    /**
+     * Add a song to the current playlist.
+     * @param song Song to be added to the playlist.
+     */
     private void addToPlaylist(Song song){
         playlistTableModel.addSong(song);
         playList.revalidate();
     }
 
+    /**
+     * Get the next song in the playlist.
+     * @param currentSong The song that is currently selected.
+     * @return The next song to be selected.
+     */
     @Override
     public Song getNextSong(Song currentSong) {
         return playlistTableModel.nextSong(currentSong);
     }
 
+    /**
+     * Set the highlighted song in the playlist to this song.
+     * @param playingSong Song to be highlighted in the playlist.
+     */
     @Override
     public void setSongHighlighting(Song playingSong) {
         int index = playlistTableModel.getSongIndex(playingSong);
         playList.setRowSelectionInterval(index, index);
     }
 
+    /**
+     * 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(getNextSong(player.getCurrentSong()));
     }
 
+    /**
+     * Set the maximum value of the seekBar.
+     * @param seconds New length of seekBar.
+     */
     public void setSeekBarDuration(int seconds){
         SwingUtilities.invokeLater(() -> seekBar.setMaximum(seconds));
     }