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diff --git a/qpid/cpp/src/qpid/broker/Observers.h b/qpid/cpp/src/qpid/broker/Observers.h
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+++ b/qpid/cpp/src/qpid/broker/Observers.h
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+#ifndef QPID_BROKER_OBSERVERS_H
+#define QPID_BROKER_OBSERVERS_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/Mutex.h"
+#include <boost/shared_ptr.hpp>
+#include <set>
+#include <algorithm>
+
+namespace qpid {
+namespace broker {
+
+/**
+ * Base class for collections of observers with thread-safe add/remove and traversal.
+ */
+template <class Observer>
+class Observers
+{
+  public:
+    typedef boost::shared_ptr<Observer> ObserverPtr;
+
+    void add(const ObserverPtr& observer) {
+        sys::Mutex::ScopedLock l(lock);
+        observers.insert(observer);
+    }
+
+    void remove(const ObserverPtr& observer) {
+        sys::Mutex::ScopedLock l(lock);
+        observers.erase(observer) ;
+    }
+
+    /** Iterate over the observers. */
+    template <class F> void each(F f) {
+        Set copy;               // Make a copy and iterate outside the lock.
+        {
+            sys::Mutex::ScopedLock l(lock);
+            copy = observers;
+        }
+        std::for_each(copy.begin(), copy.end(), f);
+    }
+
+    template <class T> boost::shared_ptr<T> findType() const {
+        sys::Mutex::ScopedLock l(lock);
+        typename Set::const_iterator i =
+            std::find_if(observers.begin(), observers.end(), &isA<T>);
+        return i == observers.end() ?
+            boost::shared_ptr<T>() : boost::dynamic_pointer_cast<T>(*i);
+    }
+
+  protected:
+    typedef std::set<ObserverPtr> Set;
+    Observers() : lock(myLock) {}
+
+    /** Specify a lock for the Observers to use */
+    Observers(sys::Mutex& l) : lock(l) {}
+
+    /** Iterate over the observers without taking the lock, caller must hold the lock */
+    template <class F> void each(F f, const sys::Mutex::ScopedLock&) {
+        std::for_each(observers.begin(), observers.end(), f);
+    }
+
+    template <class T> static bool isA(const ObserverPtr&o) {
+        return !!boost::dynamic_pointer_cast<T>(o);
+    }
+
+    mutable sys::Mutex myLock;
+    sys::Mutex& lock;
+    Set observers;
+};
+
+}} // namespace qpid::broker
+
+#endif  /*!QPID_BROKER_OBSERVERS_H*/