ProviderProbe.cs

// <copyright file="ProviderProbe.cs" company="Math.NET">
// Math.NET Numerics, part of the Math.NET Project
// https://numerics.mathdotnet.com
// https://github.com/mathnet/mathnet-numerics
//
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//
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// obtaining a copy of this software and associated documentation
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// copies of the Software, and to permit persons to whom the
// Software is furnished to do so, subject to the following
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//
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
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// OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
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using System;
using System.Diagnostics.CodeAnalysis;
using System.Threading;

namespace MathNet.Numerics.Providers
{
    public class ProviderProbe<T> where T : class
    {
        readonly bool _disabled;
        readonly Lazy<IProviderCreator<T>> _creator;

        public ProviderProbe(string typeName, bool disabled = false)
        {
            _disabled = disabled;
            _creator = new Lazy<IProviderCreator<T>>(() =>
            {
                var type = Type.GetType(typeName);
                return CreateProvider(type);
            }, LazyThreadSafetyMode.ExecutionAndPublication);
        }

        private static IProviderCreator<T> CreateProvider(
#if NET6_0_OR_GREATER
            [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicConstructors)]
#endif
            Type type)
        {
            return type == null ? null : Activator.CreateInstance(type) as IProviderCreator<T>;
        }

        public T Create()
        {
            if (_disabled)
            {
                throw new NotSupportedException("Specific Native Provider disabled by an application switch");
            }

            if (AppSwitches.DisableNativeProviders)
            {
                throw new NotSupportedException("Native Providers are disabled by an application switch");
            }

            if (AppSwitches.DisableNativeProviderProbing)
            {
                throw new NotSupportedException("Native Provider Probing is disabled by an application switch");
            }

            var creator = _creator.Value;
            if (creator is null)
            {
                throw new NotSupportedException("Native Provider Probing failed to resolve creator");
            }

            return creator.CreateProvider();
        }

        public T TryCreate()
        {
            if (_disabled || AppSwitches.DisableNativeProviderProbing || AppSwitches.DisableNativeProviders)
            {
                return null;
            }

            try
            {
                return _creator.Value?.CreateProvider();
            }
            catch
            {
                // intentionally swallow exceptions here - use the explicit variants if you're interested in why
                return null;
            }
        }
    }
}