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diff --git a/simple/simple-common/src/main/java/org/simpleframework/common/thread/SchedulerQueue.java b/simple/simple-common/src/main/java/org/simpleframework/common/thread/SchedulerQueue.java
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+/*
+ * SchedulerQueue.java February 2007
+ *
+ * Copyright (C) 2007, Niall Gallagher <niallg@users.sf.net>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or 
+ * implied. See the License for the specific language governing 
+ * permissions and limitations under the License.
+ */
+
+package org.simpleframework.common.thread;
+
+import static java.util.concurrent.TimeUnit.MILLISECONDS;
+
+import java.util.concurrent.ScheduledThreadPoolExecutor;
+import java.util.concurrent.ThreadFactory;
+import java.util.concurrent.TimeUnit;
+
+/**
+ * The <code>SchedulerQueue</code> object is used to schedule tasks 
+ * for execution. This queues the task for the requested period of 
+ * time before it is executed. It ensures that the delay is adhered 
+ * to such that tasks can be timed for execution in an accurate way.
+ * 
+ * @author Niall Gallagher
+ */
+class SchedulerQueue {
+   
+   /**
+    * This is the actual scheduler used to schedule the tasks.
+    */
+   private final ScheduledThreadPoolExecutor executor;
+   
+   /**
+    * This is the factory used to create the worker threads.
+    */
+   private final ThreadFactory factory;
+   
+   /**
+    * Constructor for the <code>SchedulerQueue</code> object. This 
+    * will create a scheduler with a fixed number of threads to use
+    * before execution. Depending on the types of task that are
+    * to be executed this should be increased for accuracy.
+    * 
+    * @param type this is the type of task to execute
+    * @param size this is the number of threads for the scheduler
+    */   
+   public SchedulerQueue(Class type, int size) {
+      this.factory = new DaemonFactory(type);
+      this.executor = new ScheduledThreadPoolExecutor(size, factory);
+   }
+   
+   /**
+    * The <code>execute</code> method is used to queue the task for
+    * execution. If all threads are busy the provided task is queued
+    * and waits until all current and outstanding tasks are finished.
+    * 
+    * @param task this is the task to be queued for execution
+    */
+   public void execute(Runnable task) {
+      executor.execute(task);
+   }
+   
+   /**
+    * This will execute the task within the executor after the time
+    * specified has expired. If the time specified is zero then it
+    * will be executed immediately. Once the scheduler has been
+    * stopped then this method will no longer accept runnable tasks.
+    * 
+    * @param task this is the task to schedule for execution
+    * @param delay the time in milliseconds to wait for execution
+    */   
+   public void execute(Runnable task, long delay) {
+      execute(task, delay, TimeUnit.MILLISECONDS);
+   }
+   
+   /**
+    * This will execute the task within the executor after the time
+    * specified has expired. If the time specified is zero then it
+    * will be executed immediately. Once the scheduler has been
+    * stopped then this method will no longer accept runnable tasks.
+    * 
+    * @param task this is the task to schedule for execution
+    * @param delay this is the delay to wait before execution
+    * @param unit this is the duration time unit to wait for
+    */   
+   public void execute(Runnable task, long delay, TimeUnit unit) {
+      executor.schedule(task, delay, unit);
+   }
+   
+   /**
+    * This is used to stop the executor by interrupting all running
+    * tasks and shutting down the threads within the pool. This will
+    * return once it has been stopped, and no further tasks will be 
+    * accepted by this pool for execution.
+    */   
+   public void stop() {
+      stop(60000);
+   }
+   
+   /**
+    * This is used to stop the executor by interrupting all running
+    * tasks and shutting down the threads within the pool. This will
+    * return once it has been stopped, and no further tasks will be 
+    * accepted by this pool for execution.
+    * 
+    * @param wait the number of milliseconds to wait for it to stop
+    */   
+   public void stop(long wait) {
+      if(!executor.isTerminated()) {
+         try {
+            executor.shutdown();
+            executor.awaitTermination(wait, MILLISECONDS);
+         } catch(Exception e) {
+            throw new IllegalStateException("Could not stop pool", e);
+         }         
+      }
+   }
+}