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diff --git a/qpid/cpp/src/qpid/broker/StatefulQueueObserver.h b/qpid/cpp/src/qpid/broker/StatefulQueueObserver.h
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+++ b/qpid/cpp/src/qpid/broker/StatefulQueueObserver.h
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+#ifndef QPID_BROKER_STATEFULQUEUEOBSERVER_H
+#define QPID_BROKER_STATEFULQUEUEOBSERVER_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/broker/QueueObserver.h"
+#include "qpid/framing/FieldTable.h"
+
+namespace qpid {
+namespace broker {
+
+/**
+ * Specialized type of QueueObserver that maintains internal state that has to
+ * be replicated across clustered brokers.
+ */
+class StatefulQueueObserver : public QueueObserver
+{
+  public:
+    StatefulQueueObserver(std::string _id) : id(_id) {}
+    virtual ~StatefulQueueObserver() {}
+
+    /** This identifier must uniquely identify this particular observer amoung
+     * all observers on a queue.  For cluster replication, this id will be used
+     * to identify the peer queue observer for synchronization across
+     * brokers.
+     */
+    const std::string& getId() const { return id; }
+
+    /** This method should return the observer's internal state as an opaque
+     * map.
+     */
+    virtual void getState(qpid::framing::FieldTable& state ) const = 0;
+
+    /** The input map represents the internal state of the peer observer that
+     * this observer should synchonize to.
+     */
+    virtual void setState(const qpid::framing::FieldTable&) = 0;
+
+
+  private:
+    std::string id;
+};
+}} // namespace qpid::broker
+
+#endif  /*!QPID_BROKER_STATEFULQUEUEOBSERVER_H*/