Newtonsoft.Json\Serialization\JsonArrayContract.cs

#region License

// Copyright (c) 2007 James Newton-King

//

// 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.

#endregion

using System;

using System.Collections.Generic;

using System.Reflection;

using Newtonsoft.Json.Utilities;

using System.Collections;

namespace Newtonsoft.Json.Serialization

{

  /// <summary>

  /// Contract details for a <see cref="Type"/> used by the <see cref="JsonSerializer"/>.

  /// </summary>

  public class JsonArrayContract : JsonContract

  {

    internal Type CollectionItemType { get; private set; }

    private readonly bool _isCollectionItemTypeNullableType;

    private readonly Type _genericCollectionDefinitionType;

    private Type _genericWrapperType;

    private MethodCall<object, object> _genericWrapperCreator;

    /// <summary>

    /// Initializes a new instance of the <see cref="JsonArrayContract"/> class.

    /// </summary>

    /// <param name="underlyingType">The underlying type for the contract.</param>

    public JsonArrayContract(Type underlyingType)

      : base(underlyingType)

    {

      if (ReflectionUtils.ImplementsGenericDefinition(underlyingType, typeof(ICollection<>), out _genericCollectionDefinitionType))

      {

        CollectionItemType = _genericCollectionDefinitionType.GetGenericArguments()[0];

      }

      else

      {

        CollectionItemType = ReflectionUtils.GetCollectionItemType(UnderlyingType);

      }

      if (CollectionItemType != null)

        _isCollectionItemTypeNullableType = ReflectionUtils.IsNullableType(CollectionItemType);

      if (IsTypeGenericCollectionInterface(UnderlyingType))

      {

        CreatedType = ReflectionUtils.MakeGenericType(typeof(List<>), CollectionItemType);

      }

    }

    internal IWrappedCollection CreateWrapper(object list)

    {

      if ((list is IList && (CollectionItemType == null || !_isCollectionItemTypeNullableType))

        || UnderlyingType.IsArray)

        return new CollectionWrapper<object>((IList)list);

      if (_genericWrapperType == null)

      {

        _genericWrapperType = ReflectionUtils.MakeGenericType(typeof(CollectionWrapper<>), CollectionItemType);

        ConstructorInfo genericWrapperConstructor = _genericWrapperType.GetConstructor(new[] { _genericCollectionDefinitionType });

        _genericWrapperCreator = JsonTypeReflector.ReflectionDelegateFactory.CreateMethodCall<object>(genericWrapperConstructor);

      }

      return (IWrappedCollection)_genericWrapperCreator(null, list);

    }

    private bool IsTypeGenericCollectionInterface(Type type)

    {

      if (!type.IsGenericType)

        return false;

      Type genericDefinition = type.GetGenericTypeDefinition();

      return (genericDefinition == typeof(IList<>)

              || genericDefinition == typeof(ICollection<>)

              || genericDefinition == typeof(IEnumerable<>));

    }

  }

}