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diff --git a/simple/simple-common/src/main/java/org/simpleframework/common/thread/Daemon.java b/simple/simple-common/src/main/java/org/simpleframework/common/thread/Daemon.java
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+++ b/simple/simple-common/src/main/java/org/simpleframework/common/thread/Daemon.java
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+/*
+ * Daemon.java February 2009
+ *
+ * Copyright (C) 2009, 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 java.util.concurrent.atomic.AtomicBoolean;
+import java.util.concurrent.atomic.AtomicReference;
+
+/**
+ * The <code>Daemon</code> object provides a named thread which will
+ * execute the <code>run</code> method when started. This offers 
+ * some convenience in that it hides the normal thread methods and 
+ * also allows the object extending this to provide the name of the 
+ * internal thread, which is given an incrementing sequence number 
+ * appended to the name provided.
+ * 
+ * @author Niall Gallagher
+ */
+public abstract class Daemon implements Runnable {
+   
+   /**
+    * This is the current thread executing this service.
+    */
+   private final AtomicReference<Thread> reference;
+   
+   /**
+    * This is the internal thread used by this daemon instance.
+    */
+   private final DaemonFactory factory;
+   
+   /**
+    * This is used to determine if the daemon is active.
+    */
+   private final AtomicBoolean active;
+   
+   /**
+    * This is the internal thread that is executed by this.
+    */
+   private final Runnable delegate;
+   
+   /**
+    * Constructor for the <code>Daemon</code> object. This will 
+    * create the internal thread and ensure it is a daemon. When it
+    * is started the name of the internal thread is set using the
+    * name of the instance as taken from <code>getName</code>. If
+    * the name provided is null then no name is set for the thread.
+    */
+   protected Daemon() {
+      this.reference = new AtomicReference<Thread>();
+      this.delegate = new RunnableDelegate(this);
+      this.factory = new DaemonFactory();
+      this.active = new AtomicBoolean();
+   }   
+   
+   /**
+    * This is used to determine if the runner is active. If it is not
+    * active then it is assumed that no thread is executing. Also, if
+    * this is extended then any executing thread to stop as soon as
+    * this method returns false.
+    * 
+    * @return this returns true if the runner is active
+    */
+   public boolean isActive() {
+      return active.get();
+   }
+   
+   /**
+    * This is used to start the internal thread. Once started the
+    * internal thread will execute the <code>run</code> method of
+    * this instance. Aside from starting the thread this will also
+    * ensure the internal thread has a unique name.
+    */
+   public void start() {
+      Class type = getClass();
+      
+      if (!active.get()) {
+         Thread thread = factory.newThread(delegate, type);
+         
+         reference.set(thread);
+         active.set(true);
+         thread.start();
+      }
+   }
+   
+   /**
+    * This is used to interrupt the internal thread. This is used
+    * when there is a need to wake the thread from a sleeping or
+    * waiting state so that some other operation can be performed.
+    * Typically this is required when killing the thread.
+    */
+   public void interrupt() {
+      Thread thread = reference.get();
+      
+      if(thread != null) {
+         thread.interrupt();
+      }
+   }   
+   
+   /**
+    * This method is used to stop the thread without forcing it to
+    * stop. It acts as a means to deactivate it. It is up to the
+    * implementor to ensure that the <code>isActive</code> method
+    * is checked to determine whether it should continue to run.
+    */
+   public void stop() {
+      active.set(false);
+   }
+   
+   /**
+    * The <code>RunnableDelegate</code> object is used to actually
+    * invoke the <code>run</code> method. A delegate is used to ensure
+    * that once the task has finished it is inactive so that it can
+    * be started again with a new thread.    
+    */
+   private class RunnableDelegate implements Runnable {      
+      
+      /**
+       * This is the runnable that is to be executed. 
+       */
+      private final Runnable task;
+      
+      /**
+       * Constructor for the <code>RunnableDelegate</code> object. The
+       * delegate requires the actual runnable that is to be executed.
+       * As soon as the task has finished the runner becomes inactive.
+       * 
+       * @param task this is the task to be executed
+       */
+      public RunnableDelegate(Runnable task) {
+         this.task = task;
+      }
+      
+      /**
+       * This is used to execute the task. Once the task has finished
+       * the runner becomes inactive and any reference to the internal
+       * thread is set to null. This ensures the runner can be started
+       * again at a later time if desired.
+       */
+      public void run() {
+         try {
+            task.run();
+         } finally {
+            reference.set(null);
+            active.set(false);
+         }
+      }
+      
+   }
+}