FieldAccessorBase.cs

#region Copyright notice and license
// Protocol Buffers - Google's data interchange format
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using System;
using System.Reflection;
using Google.Protobuf.Compatibility;

namespace Google.Protobuf.Reflection
{
    /// <summary>
    /// Base class for field accessors.
    /// </summary>
    internal abstract class FieldAccessorBase : IFieldAccessor
    {
        private readonly Func<IMessage, object> getValueDelegate;
        private readonly FieldDescriptor descriptor;

        internal FieldAccessorBase(PropertyInfo property, FieldDescriptor descriptor)
        {
            this.descriptor = descriptor;
            getValueDelegate = ReflectionUtil.CreateFuncIMessageObject(property.GetGetMethod());
        }

        public FieldDescriptor Descriptor { get { return descriptor; } }

        public object GetValue(IMessage message)
        {
            return getValueDelegate(message);
        }

        public abstract bool HasValue(IMessage message);
        public abstract void Clear(IMessage message);
        public abstract void SetValue(IMessage message, object value);
    }
}