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diff --git a/qpid/cpp/src/qpid/sys/Serializer.h b/qpid/cpp/src/qpid/sys/Serializer.h
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+++ b/qpid/cpp/src/qpid/sys/Serializer.h
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+#ifndef SERIALIZER_H
+#define SERIALIZER_H
+
+
+/*
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.
+ *
+ */
+
+
+#include "qpid/sys/Runnable.h"
+#include "qpid/sys/Monitor.h"
+#include "qpid/sys/Thread.h"
+
+#include <boost/function.hpp>
+#include <boost/noncopyable.hpp>
+
+#include <deque>
+
+namespace qpid {
+namespace sys {
+
+/**
+ * Execute tasks sequentially, queuing tasks when necessary to
+ * ensure only one thread at a time executes a task and tasks
+ * are executed in order.
+ */
+class Serializer : private boost::noncopyable, private Runnable
+{
+  public:
+    typedef boost::function<void()> Task;
+
+    /** Start a serializer.
+     *
+     * @param notifyDispatch Called when work is pending and there is no
+     * active dispatch thread. Must arrange for dispatch() to be called
+     * in some thread other than the calling thread and return. 
+     * By default the Serializer supplies its own dispatch thread.
+     *
+     * @param immediate Allow execute() to execute a task immediatly
+     * in the current thread.
+     */
+    Serializer(bool immediate=true, Task notifyDispatch=Task());
+
+    ~Serializer();
+    
+    /** 
+     * Task may be executed immediately in the calling thread if there
+     * are no other tasks pending or executing and the "immediate"
+     * paramater to the constructor was true. Otherwise task will be
+     * enqueued for execution by a dispatch thread.
+     */
+    void execute(Task task);
+
+    /** Execute pending tasks sequentially in calling thread.
+     * Drains the task queue and returns, does not block for more tasks.
+     * 
+     * @exception ShutdownException if the serializer is being destroyed.
+     */
+    void dispatch();
+
+  private:
+    enum State {
+        IDLE, ///< No threads are active.
+        EXECUTING, ///< execute() is executing a single task.
+        DISPATCHING, ///< dispatch() is draining the queue.
+        SHUTDOWN ///< Serializer is being destroyed.
+    };
+
+    void dispatch(Task&);
+    void notifyWorker();
+    void run();
+
+    Monitor lock;
+
+    State state;
+    bool immediate;
+    std::deque<Task> queue;
+    Thread worker;
+    Task notifyDispatch;
+};
+
+}} // namespace qpid::sys
+
+
+
+
+
+#endif  /*!SERIALIZER_H*/