// Protocol Buffers - Google's data interchange format
// Copyright 2008 Google Inc. All rights reserved.
// http://github.com/jskeet/dotnet-protobufs/
// Original C++/Java/Python code:
// http://code.google.com/p/protobuf/
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
using System;
using System.Reflection;
namespace Google.ProtocolBuffers.FieldAccess {
/// <summary>
/// Accessor for a repeated message field.
///
/// TODO(jonskeet): Try to extract the commonality between this and SingleMessageAccessor.
/// We almost want multiple inheritance...
/// </summary>
internal sealed class RepeatedMessageAccessor<TMessage, TBuilder> : RepeatedPrimitiveAccessor<TMessage, TBuilder>
where TMessage : IMessage<TMessage, TBuilder>
where TBuilder : IBuilder<TMessage, TBuilder> {
/// <summary>
/// The static method to create a builder for the property type. For example,
/// in a message type "Foo", a field called "bar" might be of type "Baz". This
/// method is Baz.CreateBuilder.
/// </summary>
private readonly Func<IBuilder> createBuilderDelegate;
internal RepeatedMessageAccessor(string name) : base(name) {
MethodInfo createBuilderMethod = ClrType.GetMethod("CreateBuilder", EmptyTypes);
if (createBuilderMethod == null) {
throw new ArgumentException("No public static CreateBuilder method declared in " + ClrType.Name);
}
createBuilderDelegate = ReflectionUtil.CreateStaticUpcastDelegate(createBuilderMethod);
}
/// <summary>
/// Creates a message of the appropriate CLR type from the given value,
/// which may already be of the right type or may be a dynamic message.
/// </summary>
private object CoerceType(object value) {
ThrowHelper.ThrowIfNull(value, "value");
// If it's already of the right type, we're done
if (ClrType.IsInstanceOfType(value)) {
return value;
}
// No... so let's create a builder of the right type, and merge the value in.
IMessageLite message = (IMessageLite) value;
return CreateBuilder().WeakMergeFrom(message).WeakBuild();
}
public override void SetRepeated(TBuilder builder, int index, object value) {
base.SetRepeated(builder, index, CoerceType(value));
}
public override IBuilder CreateBuilder() {
return createBuilderDelegate();
}
public override void AddRepeated(TBuilder builder, object value) {
base.AddRepeated(builder, CoerceType(value));
}
}
}