Extended the item updated event. (#14)

src/Fluxera.Entity/DomainEvents/ItemAdded.cs

@@ -18,12 +18,12 @@ public sealed class ItemAdded<TAggregateRoot, TKey> : IDomainEvent
 		/// <param name="item">The underlying item of this event.</param>
 		public ItemAdded(TAggregateRoot item)
 		{
-			this.Item = item;
+			this.AddedItem = item;
 		}
 
 		/// <summary>
-		///     Gets the underlying item.
+		///     Gets the added item.
 		/// </summary>
-		public TAggregateRoot Item { get; }
+		public TAggregateRoot AddedItem { get; }
 	}
 }

src/Fluxera.Entity/DomainEvents/ItemRemoved.cs

@@ -19,17 +19,17 @@ public sealed class ItemRemoved<TAggregateRoot, TKey> : IDomainEvent
 		/// <param name="id">The id of the underlying item of this event.</param>
 		public ItemRemoved(TAggregateRoot item, TKey id)
 		{
-			this.Item = item;
+			this.DeletedItem = item;
 			this.ID = id;
 		}
 
 		/// <summary>
-		///     Gets the underlying item.
+		///     Gets the deleted item (has no ID anymore).
 		/// </summary>
-		public TAggregateRoot Item { get; }
+		public TAggregateRoot DeletedItem { get; }
 
 		/// <summary>
-		///     Gets the id of underlying item.
+		///     Gets the id of deleted item.
 		/// </summary>
 		public TKey ID { get; }
 	}

src/Fluxera.Entity/DomainEvents/ItemUpdated.cs

@@ -15,15 +15,22 @@ public sealed class ItemUpdated<TAggregateRoot, TKey> : IDomainEvent
 		/// <summary>
 		///     Creates a new instance of the <see cref="ItemUpdated{TAggregateRoot,TKey}" /> type.
 		/// </summary>
-		/// <param name="item">The underlying item of this event.</param>
-		public ItemUpdated(TAggregateRoot item)
+		/// <param name="beforeUpdateItem">The underlying item of this event.</param>
+		/// <param name="afterUpdateItem">The underlying item of this event.</param>
+		public ItemUpdated(TAggregateRoot beforeUpdateItem, TAggregateRoot afterUpdateItem)
 		{
-			this.Item = item;
+			this.BeforeUpdateItem = beforeUpdateItem;
+			this.AfterUpdateItem = afterUpdateItem;
 		}
 
 		/// <summary>
-		///     Gets the underlying item.
+		///     Gets the item before the update.
 		/// </summary>
-		public TAggregateRoot Item { get; }
+		public TAggregateRoot BeforeUpdateItem { get; }
+
+		/// <summary>
+		///     Gets the updated item.
+		/// </summary>
+		public TAggregateRoot AfterUpdateItem { get; }
 	}
 }

src/Fluxera.Entity/Entity.cs

@@ -39,7 +39,7 @@ protected Entity()
 		///     The unique ID of the entity.
 		/// </summary>
 		[Key]
-		public virtual TKey? ID { get; set; }
+		public virtual TKey ID { get; set; }
 
 		/// <summary>
 		///     The domain events of this entity.
@@ -68,18 +68,18 @@ public virtual bool IsTransient
 		}
 
 		/// <inheritdoc />
-		public event PropertyChangedEventHandler? PropertyChanged;
+		public event PropertyChangedEventHandler PropertyChanged;
 
 		/// <inheritdoc />
-		public event PropertyChangingEventHandler? PropertyChanging;
+		public event PropertyChangingEventHandler PropertyChanging;
 
 		/// <summary>
 		///     Checks two instances of <see cref="Entity{TEntity,TKey}" /> are equal.
 		/// </summary>
 		/// <param name="left">The left item of the operator.</param>
 		/// <param name="right">The left item of the operator.</param>
 		/// <returns>True, if the instances are equal.</returns>
-		public static bool operator ==(Entity<TEntity, TKey>? left, Entity<TEntity, TKey>? right)
+		public static bool operator ==(Entity<TEntity, TKey> left, Entity<TEntity, TKey> right)
 		{
 			if(left is null)
 			{
@@ -95,13 +95,13 @@ public virtual bool IsTransient
 		/// <param name="left">The left item of the operator.</param>
 		/// <param name="right">The left item of the operator.</param>
 		/// <returns>True, if the instances are equal.</returns>
-		public static bool operator !=(Entity<TEntity, TKey>? left, Entity<TEntity, TKey>? right)
+		public static bool operator !=(Entity<TEntity, TKey> left, Entity<TEntity, TKey> right)
 		{
 			return !(left == right);
 		}
 
 		/// <inheritdoc />
-		public override bool Equals(object? obj)
+		public override bool Equals(object obj)
 		{
 			if(obj is null)
 			{
@@ -142,7 +142,7 @@ public override int GetHashCode()
 				// so we include the value object type in the hash calculation
 				int hashCode = this.GetType().GetHashCode();
 
-				foreach(object? component in this.GetEqualityComponents())
+				foreach(object component in this.GetEqualityComponents())
 				{
 					if(component != null)
 					{
@@ -173,7 +173,7 @@ public virtual Type GetUnProxiedType()
 		///     with [DomainSignature] and they will be compared automatically.
 		/// </summary>
 		/// <returns>The components to use for equality.</returns>
-		protected virtual IEnumerable<object?> GetEqualityComponents()
+		protected virtual IEnumerable<object> GetEqualityComponents()
 		{
 			PropertyAccessor[] propertyAccessors = PropertyAccessor.GetPropertyAccessors(this.GetType(),
 				property =>
@@ -192,7 +192,7 @@ public virtual Type GetUnProxiedType()
 
 			foreach(PropertyAccessor accessor in propertyAccessors)
 			{
-				object? value = accessor.Invoke(this);
+				object value = accessor.Invoke(this);
 				yield return value;
 			}
 		}
@@ -204,7 +204,7 @@ public virtual Type GetUnProxiedType()
 		/// <param name="field">The field reference to set.</param>
 		/// <param name="value">The value to set.</param>
 		/// <param name="propertyName">The name of the used property.</param>
-		protected void SetAndNotify<T>(ref T? field, T? value, [CallerMemberName] string propertyName = null!)
+		protected void SetAndNotify<T>(ref T field, T value, [CallerMemberName] string propertyName = null!)
 		{
 			if(!Equals(field, value))
 			{

src/Fluxera.Entity/PropertyAccessor.cs

@@ -4,7 +4,7 @@
 	using System.Collections.Concurrent;
 	using System.Linq;
 	using System.Reflection;
-	using Guards;
+	using Fluxera.Guards;
 	using JetBrains.Annotations;
 
 	[PublicAPI]
@@ -27,7 +27,7 @@ private PropertyAccessor(string propertyName, Func<object, object> getterFunc)
 
 		private Func<object, object> GetterFunc { get; }
 
-		public object? Invoke(object target)
+		public object Invoke(object target)
 		{
 			return this.GetterFunc.Invoke(target);
 		}
@@ -40,12 +40,12 @@ public static PropertyAccessor[] GetPropertyAccessors(Type type, Predicate<Prope
 					.Where(predicate.Invoke)
 					.Select(property =>
 					{
-						MethodInfo? getMethod = property.GetMethod;
-						Type? declaringType = property.DeclaringType;
+						MethodInfo getMethod = property.GetMethod;
+						Type declaringType = property.DeclaringType;
 						Type propertyType = property.PropertyType;
 
 						Type getMethodDelegateType = typeof(Func<,>).MakeGenericType(declaringType, propertyType);
-						Delegate? getMethodDelegate = getMethod.CreateDelegate(getMethodDelegateType);
+						Delegate getMethodDelegate = getMethod.CreateDelegate(getMethodDelegateType);
 						MethodInfo callInnerGenericMethodWithTypes = callInnerDelegateMethod.MakeGenericMethod(declaringType, propertyType);
 						Func<object, object> getter = (Func<object, object>)callInnerGenericMethodWithTypes.Invoke(null, new object[] { getMethodDelegate });