refactor lifetime

BitFaster.Caching.UnitTests/SingletonCacheTests.cs

@@ -9,41 +9,41 @@ namespace BitFaster.Caching.UnitTests
 	public class SingletonCacheTests
 	{
 		[Fact]
-		public void AcquireWithSameKeyUsingCustomComparerReturnsSameHandle()
+		public void AcquireWithSameKeyUsingCustomComparerReturnsSameLifetime()
 		{
 			var cache = new SingletonCache<string, object>(1, 3, StringComparer.OrdinalIgnoreCase);
 
-			var handle1 = cache.Acquire("foo");
-			var handle2 = cache.Acquire("FOO");
-			handle1.Value.Should().BeSameAs(handle2.Value);
-			handle1.Dispose();
-			handle2.Dispose();
+			var lifetime1 = cache.Acquire("foo");
+			var lifetime2 = cache.Acquire("FOO");
+			lifetime1.Value.Should().BeSameAs(lifetime2.Value);
+			lifetime1.Dispose();
+			lifetime2.Dispose();
 		}
 
 		[Fact]
-		public void AcquireWithSameKeyReturnsSameHandle()
+		public void AcquireWithSameKeyReturnsSameLifetime()
 		{
 			var cache = new SingletonCache<string, object>();
 
-			var handle1 = cache.Acquire("Foo");
-			var handle2 = cache.Acquire("Foo");
-			handle1.Value.Should().BeSameAs(handle2.Value);
-			handle1.Dispose();
-			handle2.Dispose();
+			var lifetime1 = cache.Acquire("Foo");
+			var lifetime2 = cache.Acquire("Foo");
+			lifetime1.Value.Should().BeSameAs(lifetime2.Value);
+			lifetime1.Dispose();
+			lifetime2.Dispose();
 		}
 
 		[Fact]
 		public void AcquireReleaseAcquireReturnsDifferentValue()
 		{
 			var cache = new SingletonCache<string, object>();
 
-			var handle1 = cache.Acquire("Foo");
-			handle1.Dispose();
+			var lifetime1 = cache.Acquire("Foo");
+			lifetime1.Dispose();
 
-			var handle2 = cache.Acquire("Foo");
-			handle2.Dispose();
+			var lifetime2 = cache.Acquire("Foo");
+			lifetime2.Dispose();
 
-			handle1.Value.Should().NotBeSameAs(handle2.Value);
+			lifetime1.Value.Should().NotBeSameAs(lifetime2.Value);
 		}
 
 		[Fact]
@@ -54,34 +54,34 @@ public async Task AcquireWithSameKeyOnTwoDifferentThreadsReturnsSameValue()
 			EventWaitHandle event1 = new EventWaitHandle(false, EventResetMode.AutoReset);
 			EventWaitHandle event2 = new EventWaitHandle(false, EventResetMode.AutoReset);
 
-			SingletonCache<string, object>.Handle handle1 = null;
-			SingletonCache<string, object>.Handle handle2 = null;
+			Lifetime<object> lifetime1 = null;
+            Lifetime<object> lifetime2 = null;
 
 			Task task1 = Task.Run(() =>
 			{
 				event1.WaitOne();
-				handle1 = cache.Acquire("Foo");
+				lifetime1 = cache.Acquire("Foo");
 				event2.Set();
 
 				event1.WaitOne();
-				handle1.Dispose();
+				lifetime1.Dispose();
 				event2.Set();
 			});
 
 			Task task2 = Task.Run(() =>
 			{
 				event1.Set();
 				event2.WaitOne();
-				handle2 = cache.Acquire("Foo");
+				lifetime2 = cache.Acquire("Foo");
 
 				event1.Set();
 				event2.WaitOne();
-				handle2.Dispose();
+				lifetime2.Dispose();
 			});
 
 			await Task.WhenAll(task1, task2);
 
-			handle1.Value.Should().BeSameAs(handle2.Value);
+			lifetime1.Value.Should().BeSameAs(lifetime2.Value);
 		}
 
 		[Fact]
@@ -99,9 +99,9 @@ public async Task AcquireWithSameKeyOnManyDifferentThreadsReturnsSameValue()
 				{
 					for (int i = 0; i < 100000; i++)
 					{
-						using (var handle = cache.Acquire("Foo"))
+						using (var lifetime = cache.Acquire("Foo"))
 						{
-							lock (handle.Value)
+							lock (lifetime.Value)
 							{
 								int result = Interlocked.Increment(ref count);
 								result.Should().Be(1);
@@ -120,7 +120,7 @@ public void WhenValueIsDisposableItIsDisposedWhenReleased()
 		{
 			var cache = new SingletonCache<string, DisposeTest>();
 
-			using (var handle = cache.Acquire("Foo"))
+			using (var lifetime = cache.Acquire("Foo"))
 			{
 				DisposeTest.WasDisposed.Should().BeFalse();
 			}

BitFaster.Caching/Lifetime.cs

@@ -0,0 +1,29 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace BitFaster.Caching
+{
+    public class Lifetime<T> : IDisposable
+    {
+        private readonly Action onDisposeAction;
+        private bool isDisposed;
+
+        public Lifetime(T value, Action onDisposeAction)
+        {
+            this.Value = value;
+            this.onDisposeAction = onDisposeAction;
+        }
+
+        public T Value { get; }
+
+        public void Dispose()
+        {
+            if (!this.isDisposed)
+            {
+                this.onDisposeAction();
+                this.isDisposed = true;
+            }
+        }
+    }
+}

BitFaster.Caching/Scoped.cs

@@ -21,7 +21,7 @@ public Scoped(T value)
             this.refCount = new ReferenceCount<T>(value);
         }
 
-        public Lifetime CreateLifetime()
+        public Lifetime<T> CreateLifetime()
         {
             if (this.isDisposed)
             {
@@ -38,7 +38,7 @@ public Lifetime CreateLifetime()
                 if (oldRefCount == Interlocked.CompareExchange(ref this.refCount, newRefCount, oldRefCount))
                 {
                     // When Lease is disposed, it calls DecrementReferenceCount
-                    return new Lifetime(oldRefCount.Value, this.DecrementReferenceCount);
+                    return new Lifetime<T>(oldRefCount.Value, this.DecrementReferenceCount);
                 }
             }
         }
@@ -70,28 +70,5 @@ public void Dispose()
                 this.isDisposed = true;
             }
         }
-
-        public class Lifetime : IDisposable
-        {
-            private readonly Action onDisposeAction;
-            private bool isDisposed;
-
-            public Lifetime(T value, Action onDisposeAction)
-            {
-                this.Value = value;
-                this.onDisposeAction = onDisposeAction;
-            }
-
-            public T Value { get; }
-
-            public void Dispose()
-            {
-                if (!this.isDisposed)
-                {
-                    this.onDisposeAction();
-                    this.isDisposed = true;
-                }
-            }
-        }
     }
 }

BitFaster.Caching/SingletonCache.cs

@@ -27,13 +27,13 @@ public SingletonCache(int concurrencyLevel, int capacity, IEqualityComparer<TKey
             this.cache = new ConcurrentDictionary<TKey, ReferenceCount<TValue>>(concurrencyLevel, capacity, comparer);
         }
 
-        public Handle Acquire(TKey key, Func<TKey, TValue> valueFactory)
+        public Lifetime<TValue> Acquire(TKey key, Func<TKey, TValue> valueFactory)
         {
             var refCount = this.cache.AddOrUpdate(key,
                     (_) => new ReferenceCount<TValue>(valueFactory(_)),
                     (_, existingRefCount) => existingRefCount.IncrementCopy());
 
-            return new Handle(key, refCount.Value, this);
+            return new Lifetime<TValue>(refCount.Value, () => this.Release(key));
         }
 
         private void Release(TKey key)
@@ -46,7 +46,6 @@ private void Release(TKey key)
                 {
                     if (newRefCount.Count == 0)
                     {
-                        // This will remove from dictionary only if key and the value with ReferenceCount (== 0) matches (under a lock)
                         if (((IDictionary<TKey, ReferenceCount<TValue>>)this.cache).Remove(new KeyValuePair<TKey, ReferenceCount<TValue>>(key, newRefCount)))
                         {
                             if (newRefCount.Value is IDisposable d)
@@ -59,36 +58,5 @@ private void Release(TKey key)
                 }
             }
         }
-
-        public sealed class Handle : IDisposable
-        {
-            private TKey key;
-            private TValue value;
-            private SingletonCache<TKey, TValue> cache;
-
-            public Handle(TKey key, TValue value, SingletonCache<TKey, TValue> cache)
-            {
-                this.key = key;
-                this.value = value;
-                this.cache = cache;
-            }
-
-            public TValue Value
-            {
-                get
-                {
-                    return this.value;
-                }
-            }
-
-            public void Dispose()
-            {
-                if (this.cache != null)
-                {
-                    this.cache.Release(this.key);
-                    this.cache = null;
-                }
-            }
-        }
     }
 }

BitFaster.Caching/SingletonCacheExtensions.cs

@@ -6,7 +6,7 @@ namespace BitFaster.Caching
 {
     public static class SingletonCacheExtensions
     {
-        public static SingletonCache<TKey, TValue>.Handle Acquire<TKey, TValue>(this SingletonCache<TKey, TValue> cache, TKey key) 
+        public static Lifetime<TValue> Acquire<TKey, TValue>(this SingletonCache<TKey, TValue> cache, TKey key) 
             where TValue : new()
         {
             return cache.Acquire(key, _ => new TValue());