1 files changed, 59 insertions, 0 deletions
diff --git a/qpid/cpp/src/qpid/broker/LegacyLVQ.h b/qpid/cpp/src/qpid/broker/LegacyLVQ.h
new file mode 100644
index 0000000000..dd0fd7aaec
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+++ b/qpid/cpp/src/qpid/broker/LegacyLVQ.h
@@ -0,0 +1,59 @@
+#ifndef QPID_BROKER_LEGACYLVQ_H
+#define QPID_BROKER_LEGACYLVQ_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/MessageMap.h"
+#include <memory>
+
+namespace qpid {
+namespace broker {
+class Broker;
+
+/**
+ * This class encapsulates the behaviour of the old style LVQ where a
+ * message replacing another messages for the given key will use the
+ * position in the queue of the previous message. This however causes
+ * problems for browsing. Either browsers stop the coalescing of
+ * messages by key (default) or they may mis updates (if the no-browse
+ * option is specified).
+ */
+class LegacyLVQ : public MessageMap
+{
+  public:
+    LegacyLVQ(const std::string& key, bool noBrowse = false, Broker* broker = 0);
+    bool remove(const framing::SequenceNumber&, QueuedMessage&);
+    bool next(const framing::SequenceNumber&, QueuedMessage&);
+    bool push(const QueuedMessage& added, QueuedMessage& removed);
+    void removeIf(Predicate);
+    void setNoBrowse(bool);
+    static std::auto_ptr<Messages> updateOrReplace(std::auto_ptr<Messages> current, 
+                                                   const std::string& key, bool noBrowse,
+                                                   Broker* broker);
+  protected:
+    bool noBrowse;
+    Broker* broker;
+
+    const QueuedMessage& replace(const QueuedMessage&, const QueuedMessage&);
+};
+}} // namespace qpid::broker
+
+#endif  /*!QPID_BROKER_LEGACYLVQ_H*/