46 lines
1.6 KiB
C#
46 lines
1.6 KiB
C#
|
// Copyright (c) All contributors. All rights reserved.
|
||
|
|
// Licensed under the MIT license. See LICENSE file in the project root for full license information.
|
||
|
|
|
||
|
|
using System;
|
||
|
|
using System.Reflection;
|
||
|
|
using MessagePack.Formatters;
|
||
|
|
|
||
|
|
namespace MessagePack.Internal
|
||
|
|
{
|
||
|
|
internal static class ResolverUtilities
|
||
|
|
{
|
||
|
|
internal static IMessagePackFormatter ActivateFormatter(Type formatterType, object[] args = null)
|
||
|
|
{
|
||
|
|
if (args == null || args.Length == 0)
|
||
|
|
{
|
||
|
|
if (formatterType.GetConstructor(Type.EmptyTypes) is ConstructorInfo ctor)
|
||
|
|
{
|
||
|
|
return (IMessagePackFormatter)ctor.Invoke(Array.Empty<object>());
|
||
|
|
}
|
||
|
|
else if (FetchSingletonField(formatterType) is FieldInfo instance)
|
||
|
|
{
|
||
|
|
return (IMessagePackFormatter)instance.GetValue(null);
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
throw new MessagePackSerializationException($"The {formatterType.FullName} formatter has no default constructor nor implements the singleton pattern.");
|
||
|
|
}
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
return (IMessagePackFormatter)Activator.CreateInstance(formatterType, args);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
internal static FieldInfo FetchSingletonField(Type formatterType)
|
||
|
|
{
|
||
|
|
if (formatterType.GetField("Instance", BindingFlags.Static | BindingFlags.Public) is FieldInfo fieldInfo && fieldInfo.IsInitOnly)
|
||
|
|
{
|
||
|
|
return fieldInfo;
|
||
|
|
}
|
||
|
|
|
||
|
|
return null;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|