1 files changed, 36 insertions, 2 deletions
diff --git a/src/com/isode/stroke/streamstack/WhitespacePingLayer.java b/src/com/isode/stroke/streamstack/WhitespacePingLayer.java
index 3a1805c..95da051 100644
--- a/src/com/isode/stroke/streamstack/WhitespacePingLayer.java
+++ b/src/com/isode/stroke/streamstack/WhitespacePingLayer.java
@@ -4,29 +4,58 @@
  * See Documentation/Licenses/GPLv3.txt for more information.
  */
 /*
- * Copyright (c) 2011, Isode Limited, London, England.
+ * Copyright (c) 2011-2016, Isode Limited, London, England.
  * All rights reserved.
  */
 package com.isode.stroke.streamstack;
 
+import java.util.logging.Logger;
+
 import com.isode.stroke.base.SafeByteArray;
 import com.isode.stroke.network.Timer;
 import com.isode.stroke.network.TimerFactory;
+import com.isode.stroke.signals.SignalConnection;
 import com.isode.stroke.signals.Slot;
 
 public class WhitespacePingLayer extends StreamLayer {
 
     private static final int TIMEOUT_MILLISECONDS = 60000;
+    
+    private final Logger logger = Logger.getLogger(this.getClass().getName());
 
     public WhitespacePingLayer(TimerFactory timerFactory) {
         isActive = false;
         timer = timerFactory.createTimer(TIMEOUT_MILLISECONDS);
-        timer.onTick.connect(new Slot() {
+        onTickConnection = timer.onTick.connect(new Slot() {
            public void call() {
                handleTimerTick();
            }
         });
     }
+    
+    @Override
+    protected void finalize() throws Throwable {
+        try {
+            destroy();
+        }
+        finally {
+            super.finalize();
+        }
+    }
+
+    /**
+     * This replaces the C++ destructor. After calling this object should not be used again.
+     * If any methods are called after they may throw {@link NullPointerException}
+     */
+    public void destroy() {
+        if (isActive && timer != null) {
+            logger.finer("WhitespacePingLayer still active at destruction");
+            timer.stop();
+        }
+        onTickConnection.disconnect();
+        timer = null;
+        isActive = false;
+    }
 
     public void writeData(SafeByteArray data) {
         writeDataToChildLayer(data);
@@ -37,6 +66,9 @@ public class WhitespacePingLayer extends StreamLayer {
     }
 
     private void handleTimerTick() {
+        if (timer == null) {
+            return;
+        }
         timer.stop();
         writeDataToChildLayer(new SafeByteArray(" "));
         timer.start();
@@ -58,4 +90,6 @@ public class WhitespacePingLayer extends StreamLayer {
 
     private boolean isActive;
     private Timer timer;
+
+    private final SignalConnection onTickConnection;
 }