implement api stop function, improve demo code, version 1.0.1

Author: LabyStudio

README.md

@@ -37,42 +37,50 @@ if (api.hasPosition()) {
 
 Register a listener to get notified when the song changes:
 ```java
+SpotifyAPI api = SpotifyAPIFactory.create();
 api.registerListener(new SpotifyListener() {
     @Override
     public void onConnect() {
         System.out.println("Connected to Spotify!");
     }
-
+    
     @Override
     public void onTrackChanged(Track track) {
-        System.out.println("Track changed: [" + track.getId() + "] " + track.getName() + " - " + track.getArtist() + " (" + formatDuration(track.getLength()) + ")");
+        System.out.printf("Track changed: %s (%s)\n", track, formatDuration(track.getLength()));
     }
-
+    
     @Override
     public void onPositionChanged(int position) {
-        if (api.getTrack() == null) {
+        if (!api.hasTrack()) {
             return;
         }
-
+        
         int length = api.getTrack().getLength();
         float percentage = 100.0F / length * position;
-
-        System.out.println("Seek: " + (int) percentage + "% (" + formatDuration(position) + " / " + formatDuration(length) + ")");
+        
+        System.out.printf(
+            "Position changed: %s of %s (%d%%)\n",
+            formatDuration(position),
+            formatDuration(length),
+            (int) percentage
+        );
     }
-
+    
     @Override
     public void onPlayBackChanged(boolean isPlaying) {
-        System.out.println(isPlaying ? "Playing" : "Paused");
+        System.out.println(isPlaying ? "Song started playing" : "Song stopped playing");
     }
-
+    
     @Override
     public void onSync() {
-
+        
     }
-
+    
     @Override
     public void onDisconnect(Exception exception) {
         System.out.println("Disconnected: " + exception.getMessage());
+        
+        // api.stop();
     }
 });
 ```

build.gradle

@@ -4,7 +4,7 @@ plugins {
 }
 
 group 'de.labystudio'
-version '1.0.0'
+version '1.0.1'
 
 compileJava {
     sourceCompatibility = '1.8'

src/main/java/de/labystudio/spotifyapi/SpotifyAPI.java

@@ -72,4 +72,10 @@ default boolean hasTrack() {
      * @param listener the listener to register
      */
     void registerListener(SpotifyListener listener);
+
+    /**
+     * Disconnect from the Spotify application and stop all background tasks.
+     * It will also remove all listeners.
+     */
+    void stop();
 }

src/main/java/de/labystudio/spotifyapi/platform/AbstractSpotifyAPI.java

@@ -23,4 +23,8 @@ public void registerListener(SpotifyListener listener) {
         this.listeners.add(listener);
     }
 
+    @Override
+    public void stop() {
+        this.listeners.clear();
+    }
 }

src/main/java/de/labystudio/spotifyapi/platform/windows/WinSpotifyAPI.java

@@ -10,6 +10,7 @@
 
 import java.util.Objects;
 import java.util.concurrent.Executors;
+import java.util.concurrent.ScheduledFuture;
 
 /**
  * Windows implementation of the SpotifyAPI.
@@ -29,18 +30,25 @@ public class WinSpotifyAPI extends AbstractSpotifyAPI {
     private long lastTimePositionUpdated;
     private boolean positionKnown = false;
 
+    private ScheduledFuture<?> task;
+
     /**
      * Initialize the SpotifyAPI Windows implementation.
      * It will create a task that will update the current track and position every second.
      *
      * @return the initialized SpotifyAPI
+     * @throws IllegalStateException if the API is already initialized
      */
     public SpotifyAPI initialize() {
+        if (this.task != null) {
+            throw new IllegalStateException("The SpotifyAPI is already initialized");
+        }
+
         // Initial tick
         this.onTick();
 
         // Start task to update every second
-        Executors.newScheduledThreadPool(1).scheduleWithFixedDelay(
+        this.task = Executors.newScheduledThreadPool(1).scheduleWithFixedDelay(
                 this::onTick, 1, 1, java.util.concurrent.TimeUnit.SECONDS
         );
 
@@ -150,6 +158,21 @@ public boolean isConnected() {
         return this.process != null && this.process.isOpen();
     }
 
+    @Override
+    public void stop() {
+        super.stop();
+
+        if (this.task != null) {
+            this.task.cancel(true);
+            this.task = null;
+        }
+
+        if (this.process != null) {
+            this.process.close();
+            this.process = null;
+        }
+    }
+
     /**
      * Checks if the given track ID is valid.
      * A track ID is valid if there are no characters with a value of zero.

src/test/java/SpotifyTest.java

@@ -29,24 +29,29 @@ public void onConnect() {
 
             @Override
             public void onTrackChanged(Track track) {
-                System.out.println("Track changed: [" + track.getId() + "] " + track.getName() + " - " + track.getArtist() + " (" + formatDuration(track.getLength()) + ")");
+                System.out.printf("Track changed: %s (%s)\n", track, formatDuration(track.getLength()));
             }
 
             @Override
             public void onPositionChanged(int position) {
-                if (api.getTrack() == null) {
+                if (!api.hasTrack()) {
                     return;
                 }
 
                 int length = api.getTrack().getLength();
                 float percentage = 100.0F / length * position;
 
-                System.out.println("Seek: " + (int) percentage + "% (" + formatDuration(position) + " / " + formatDuration(length) + ")");
+                System.out.printf(
+                        "Position changed: %s of %s (%d%%)\n",
+                        formatDuration(position),
+                        formatDuration(length),
+                        (int) percentage
+                );
             }
 
             @Override
             public void onPlayBackChanged(boolean isPlaying) {
-                System.out.println(isPlaying ? "Playing" : "Paused");
+                System.out.println(isPlaying ? "Song started playing" : "Song stopped playing");
             }
 
             @Override
@@ -57,6 +62,8 @@ public void onSync() {
             @Override
             public void onDisconnect(Exception exception) {
                 System.out.println("Disconnected: " + exception.getMessage());
+
+                // api.stop();
             }
         });
     }