--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Plugin/MemoryCache.h	Wed Mar 22 16:13:52 2017 +0100
@@ -0,0 +1,75 @@
+/**
+ * Advanced authorization plugin for Orthanc
+ * Copyright (C) 2017 Osimis, Belgium
+ *
+ * This program is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU Affero General Public License
+ * as published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Affero General Public License for more details.
+ * 
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ **/
+
+#pragma once
+
+#include "ICacheFactory.h"
+#include "../Resources/Orthanc/Core/Cache/LeastRecentlyUsedIndex.h"
+
+#include <boost/thread/mutex.hpp>
+
+namespace OrthancPlugins
+{
+  class MemoryCache : public ICache
+  {
+  public:
+    class Factory : public ICacheFactory
+    {
+    private:
+      unsigned int   maxSize_;
+      
+    public:
+      Factory(unsigned int maxSize) :
+        maxSize_(maxSize)
+      {
+      }
+      
+      virtual ICache *Create()
+      {
+        return new MemoryCache(maxSize_);
+      }
+    };
+    
+  private:
+    class Payload;
+    
+    typedef Orthanc::LeastRecentlyUsedIndex<std::string, Payload*>  Index;
+
+    boost::mutex  mutex_;
+    unsigned int  maxSize_;
+    Index         index_;
+   
+    void RemoveOldest();
+
+    void InvalidateInternal(const std::string& key);
+    
+  public:
+    MemoryCache(unsigned int maxSize);
+    
+    ~MemoryCache();
+
+    virtual void Invalidate(const std::string& key);
+
+    virtual void Store(const std::string& key,
+                       const std::string& value,
+                       unsigned int expiration /* in seconds */);
+
+    virtual bool Retrieve(std::string& value,
+                          const std::string& key);
+  };
+}