BUG 34413423 - [33982984->14.1.1.0.10] Service.OnExit() may throw NPE…

… intermittently (main.net cl 91143 --> 14.1.1.0)

[git-p4: depot-paths = "//dev/release.net/coherence-net-v14.1.1.0/": change = 94496]

src/Coherence/Util/Daemon/Daemon.cs

@@ -590,7 +590,7 @@ public virtual void Stop()
             // Once IsExiting is set the daemon's thread will attempt to clear any interrupts and then proceed to OnExit.
             // In order to ensure that this doesn't occur before we actually get to interrupt the thread we synchronize this method
             // as well as Run's call to clear the interrupt.
-            lock (ExitMonitor)
+            using (BlockingLock l = BlockingLock.Lock(ExitMonitor))
             {
                 // only go through Stop() once to prevent spurious interrupts during OnExit()
                 if (!IsExiting)
@@ -611,6 +611,45 @@ public virtual void Stop()
             }
         }
 
+        /// <summary>
+        /// Wait for the Daemon thread to stop.
+        /// </summary>
+        ///
+        /// <param name="millis">
+        /// The number of milliseconds to wait for, or zero for infinite.
+        /// </param>
+        /// 
+        /// <returns>
+        /// <b>true</b> if the thread is no longer running.
+        /// </returns>
+        ///
+        /// <since>Coherence 14.1.2.0</since>
+        public virtual bool Join(int millis)
+        {
+            try
+            {
+                Thread thread = this.Thread;
+                if (thread != null)
+                {
+                    if (millis > 0)
+                    {
+                        thread.Join(millis);
+                    }
+                    else
+                    {
+                        thread.Join();
+                    }
+                    return !thread.IsAlive;
+                }
+                return true;
+            }
+            catch (ThreadInterruptedException)
+            {
+                Thread.CurrentThread.Interrupt();
+                return false;
+            }
+        }
+
         /// <summary>
         /// This method is called right after this daemon's thread starts.
         /// </summary>
@@ -669,7 +708,7 @@ public virtual void Run()
                     try
                     {
                         // see comment in Stop()
-                        lock (ExitMonitor)
+                        using (BlockingLock l = BlockingLock.Lock(ExitMonitor))
                         {
                             try
                             {

src/Coherence/Util/Daemon/QueueProcessor/Service/Service.cs

@@ -647,7 +647,7 @@ protected override void OnExit()
                 // give the chance for the daemon to drain it's queue
                 try
                 {
-                    daemon.Thread.Join(1000);
+                    daemon.Join(1000);
                 }
                 catch (ThreadInterruptedException)
                 {