solve issue #1761 (AssertionError in ALAudioRenderer) (#1762)

* solve issue #1761 (AssertionError in ALAudioRenderer)

* add a test for issue #1761

Author: stephengold

jme3-core/src/main/java/com/jme3/audio/openal/ALAudioRenderer.java

@@ -989,21 +989,11 @@ public void updateInDecoderThread(float tpf) {
             // Keep filling data (even if we are stopped / paused)
             boolean buffersWereFilled = fillStreamingSource(sourceId, stream, src.isLooping());
 
-            if (buffersWereFilled) {
-                if (oalStatus == Status.Stopped && jmeStatus == Status.Playing) {
-                    // The source got stopped due to buffer starvation.
-                    // Start it again.
-                    logger.log(Level.WARNING, "Buffer starvation "
-                                            + "occurred while playing stream");
-                    al.alSourcePlay(sourceId);
-                } else {
-                    // Buffers were filled, stream continues to play.
-                    if (oalStatus == Status.Playing && jmeStatus == Status.Playing) {
-                        // Nothing to do.
-                    } else {
-                        throw new AssertionError();
-                    }
-                }
+            if (buffersWereFilled && oalStatus == Status.Stopped && jmeStatus == Status.Playing) {
+                // The source got stopped due to buffer starvation.
+                // Start it again.
+                logger.log(Level.WARNING, "Buffer starvation occurred while playing stream");
+                al.alSourcePlay(sourceId);
             }
         }
 

jme3-examples/src/main/java/jme3test/audio/TestIssue1761.java

@@ -0,0 +1,86 @@
+/*
+ * Copyright (c) 2009-2022 jMonkeyEngine
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ *
+ * * Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in the
+ *   documentation and/or other materials provided with the distribution.
+ *
+ * * Neither the name of 'jMonkeyEngine' nor the names of its contributors
+ *   may be used to endorse or promote products derived from this software
+ *   without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package jme3test.audio;
+
+import com.jme3.app.SimpleApplication;
+import com.jme3.asset.plugins.UrlLocator;
+import com.jme3.audio.AudioData;
+import com.jme3.audio.AudioNode;
+import java.util.Random;
+
+/**
+ * Stress test to reproduce JME issue #1761 (AssertionError in ALAudioRenderer).
+ *
+ * <p>After some network delay, a song will play,
+ * albeit slowly and in a broken fashion.
+ * If the issue is solved, the song will play all the way through.
+ * If the issue is present, an AssertionError will be thrown, usually within a
+ * second of the song starting.
+ */
+public class TestIssue1761 extends SimpleApplication {
+
+    private AudioNode audioNode;
+    final private Random random = new Random();
+
+    /**
+     * Main entry point for the TestIssue1761 application.
+     *
+     * @param unused array of command-line arguments
+     */
+    public static void main(String[] unused) {
+        TestIssue1761 test = new TestIssue1761();
+        test.start();
+    }
+
+    @Override
+    public void simpleInitApp() {
+        assetManager.registerLocator(
+                "https://web.archive.org/web/20170625151521if_/http://www.vorbis.com/music/",
+                UrlLocator.class);
+        audioNode = new AudioNode(assetManager, "Lumme-Badloop.ogg",
+                AudioData.DataType.Stream);
+        audioNode.setPositional(false);
+        audioNode.play();
+    }
+
+    @Override
+    public void simpleUpdate(float tpf) {
+        /*
+         * Randomly pause and restart the audio.
+         */
+        if (random.nextInt(2) == 0) {
+            audioNode.pause();
+        } else {
+            audioNode.play();
+        }
+    }
+}