protobuf/csharp/src/Google.Protobuf/Reflection/ExtensionAccessor.cs

#region Copyright notice and license
// Protocol Buffers - Google's data interchange format
// Copyright 2008 Google Inc.  All rights reserved.
// https://developers.google.com/protocol-buffers/
//
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//
//     * Redistributions of source code must retain the above copyright
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// in the documentation and/or other materials provided with the
// distribution.
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// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
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#endregion

namespace Google.Protobuf.Reflection
{
    internal sealed class ExtensionAccessor : IFieldAccessor
    {
        private readonly Extension extension;
        private readonly ReflectionUtil.IExtensionReflectionHelper helper;

        internal ExtensionAccessor(FieldDescriptor descriptor)
        {
            Descriptor = descriptor;
            extension = descriptor.Extension;
            helper = ReflectionUtil.CreateExtensionHelper(extension);
        }

        public FieldDescriptor Descriptor { get; }

        public void Clear(IMessage message)
        {
            helper.ClearExtension(message);
        }

        public bool HasValue(IMessage message)
        {
            return helper.HasExtension(message);
        }

        public object GetValue(IMessage message)
        {
            return helper.GetExtension(message);
        }

        public void SetValue(IMessage message, object value)
        {
            helper.SetExtension(message, value);
        }
    }
}