Re: [Banshee-List] Track dictionary in TrackListDatabaseModel

["Gabriel Burt" <gabriel burt gmail com>]

On Jan 5, 2008 5:33 AM, LCID Fire <lcid-fire gmx net> wrote:
> I was looking into TrackListDatabaseModel and wondered why the tracks
> are managed in a Dictionary?
> Currently it's defined like:
> private Dictionary<int, LibraryTrackInfo> tracks = new Dictionary<int,
> LibraryTrackInfo>();

Unless I've misunderstood what you're talking about,
TrackListDatabaseModel in trunk does not have a dictionary itself, but
has one via it's cache adapter.  It is possible to implement the cache
adapter with an array, and I in fact I wrote a patch a couple weeks
ago to test it.  I've attached the patch.

Gabriel

Index: src/Core/Hyena/Makefile.am
===================================================================
--- src/Core/Hyena/Makefile.am	(revision 2916)
+++ src/Core/Hyena/Makefile.am	(working copy)
@@ -19,12 +19,15 @@
 	Hyena.Data.Query/QueryTermNode.cs \
 	Hyena.Data.Query/QueryToken.cs \
 	Hyena.Data.Query/SqlQueryGenerator.cs \
+	Hyena.Data/ArrayModelCache.cs \
 	Hyena.Data/CacheableModelAdapter.cs \
 	Hyena.Data/ColumnDescription.cs \
+	Hyena.Data/DictionaryModelCache.cs \
 	Hyena.Data/ICacheableModel.cs \
 	Hyena.Data/ICareAboutView.cs \
 	Hyena.Data/IFilterable.cs \
 	Hyena.Data/IListModel.cs \
+	Hyena.Data/IModelCache.cs \
 	Hyena.Data/IPropertyStoreExpose.cs \
 	Hyena.Data/ISortable.cs \
 	Hyena.Data/ISortableColumn.cs \
Index: src/Core/Hyena/Hyena.Data/CacheableModelAdapter.cs
===================================================================
--- src/Core/Hyena/Hyena.Data/CacheableModelAdapter.cs	(revision 2916)
+++ src/Core/Hyena/Hyena.Data/CacheableModelAdapter.cs	(working copy)
@@ -34,26 +34,27 @@
     public abstract class CacheableModelAdapter<T>
     {
         private ICacheableModel model;
-        private Dictionary<int, T> cache = new Dictionary<int, T> ();
+        private IModelCache<T> cache;
 
-        public CacheableModelAdapter (ICacheableModel model)
+        public CacheableModelAdapter (ICacheableModel model, IModelCache<T> cache)
         {
             this.model = model;
+            this.cache = cache;
         }
 
-        protected virtual Dictionary<int, T> Cache {
+        protected virtual IModelCache<T> Cache {
             get { return cache; }
         }
 
         public virtual T GetValue (int index)
         {
-            if (Cache.ContainsKey (index))
-                return Cache[index];
-            
+            if (cache.ContainsKey (index))
+                return cache[index];
+
             FetchSet (index, model.FetchCount);
             
-            if (Cache.ContainsKey (index))
-                return Cache[index];
+            if (cache.ContainsKey (index))
+                return cache[index];
             
             return default (T);
         }
@@ -71,7 +72,7 @@
 
         protected void InvalidateManagedCache ()
         {
-            Cache.Clear ();
+            cache.Clear ();
         }
     }
 }
Index: src/Core/Banshee.Services/Banshee.Collection.Database/BansheeCacheableModelAdapter.cs
===================================================================
--- src/Core/Banshee.Services/Banshee.Collection.Database/BansheeCacheableModelAdapter.cs	(revision 2916)
+++ src/Core/Banshee.Services/Banshee.Collection.Database/BansheeCacheableModelAdapter.cs	(working copy)
@@ -53,7 +53,8 @@
         private static bool cache_initialized = false;
 
         public BansheeCacheableModelAdapter (BansheeDbConnection connection, IDatabaseModel<T> model) 
-            : base ((ICacheableModel) model)
+            : base ((ICacheableModel) model, new ArrayModelCache<T> ((ICacheableModel) model))
+            //: base ((ICacheableModel) model, new DictionaryModelCache<T> ())
         {
             this.db_model = model;
             this.connection = connection;
--- /dev/null	2007-12-22 01:09:22.000000000 -0600
+++ src/Core/Hyena/Hyena.Data/IModelCache.cs	2007-12-20 13:36:22.000000000 -0600
@@ -0,0 +1,41 @@
+//
+// IModelCache.cs
+//
+// Author:
+//   Gabriel Burt <gburt novell com>
+//
+// Copyright (C) 2007 Novell, Inc.
+//
+// Permission is hereby granted, free of charge, to any person obtaining
+// a copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to
+// permit persons to whom the Software is furnished to do so, subject to
+// the following conditions:
+//
+// The above copyright notice and this permission notice shall be
+// included in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+//
+
+using System;
+using System.Collections.Generic;
+
+namespace Hyena.Data
+{
+    public interface IModelCache<T>
+    {
+        bool ContainsKey (int i);
+        void Add (int i, T item);
+        T this[int i] { get; }
+        void Clear ();
+    }
+}
--- /dev/null	2007-12-22 01:09:22.000000000 -0600
+++ src/Core/Hyena/Hyena.Data/ArrayModelCache.cs	2007-12-20 14:02:34.000000000 -0600
@@ -0,0 +1,78 @@
+//
+// ArrayModelCache.cs
+//
+// Author:
+//   Gabriel Burt <gburt novell com>
+//
+// Copyright (C) 2007 Novell, Inc.
+//
+// Permission is hereby granted, free of charge, to any person obtaining
+// a copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to
+// permit persons to whom the Software is furnished to do so, subject to
+// the following conditions:
+//
+// The above copyright notice and this permission notice shall be
+// included in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+//
+
+using System;
+
+namespace Hyena.Data
+{
+    public class ArrayModelCache<T> : IModelCache<T>
+    {
+        private ICacheableModel model;
+        private T [] cache;
+        private int offset = -1;
+        private int limit = 0;
+
+        public ArrayModelCache (ICacheableModel model)
+        {
+            this.model = model;
+            cache = new T [model.FetchCount];
+        }
+
+        public bool ContainsKey (int i)
+        {
+            return (i >= offset &&
+                    i <= (offset + limit));
+        }
+
+        public void Add (int i, T item)
+        {
+            if (cache.Length != model.FetchCount) {
+                cache = new T [model.FetchCount];
+                Clear ();
+            }
+
+            if (offset == -1 || i < offset || i >= (offset + cache.Length)) {
+                offset = i;
+                limit = 0;
+            }
+
+            cache [i - offset] = item;
+            limit++;
+        }
+
+        public T this [int i] {
+            get { return cache [i - offset]; }
+        }
+
+        public void Clear ()
+        {
+            offset = -1;
+            limit = 0;
+        }
+    }
+}
--- /dev/null	2007-12-22 01:09:22.000000000 -0600
+++ src/Core/Hyena/Hyena.Data/DictionaryModelCache.cs	2007-12-20 13:37:34.000000000 -0600
@@ -0,0 +1,61 @@
+//
+// DictionaryModelCache.cs
+//
+// Author:
+//   Gabriel Burt <gburt novell com>
+//
+// Copyright (C) 2007 Novell, Inc.
+//
+// Permission is hereby granted, free of charge, to any person obtaining
+// a copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to
+// permit persons to whom the Software is furnished to do so, subject to
+// the following conditions:
+//
+// The above copyright notice and this permission notice shall be
+// included in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+//
+
+using System;
+using System.Collections.Generic;
+
+namespace Hyena.Data
+{
+    public class DictionaryModelCache<T> : IModelCache<T>
+    {
+        private Dictionary<int, T> cache = new Dictionary<int, T> ();
+
+        public DictionaryModelCache ()
+        {
+        }
+
+        public bool ContainsKey (int i)
+        {
+            return cache.ContainsKey (i);
+        }
+
+        public void Add (int i, T item)
+        {
+            cache.Add (i, item);
+        }
+
+        public T this [int i] {
+            get { return cache [i]; }
+        }
+
+        public void Clear ()
+        {
+            cache.Clear ();
+        }
+    }
+}