diff options
Diffstat (limited to 'csharp/src/Google.Protobuf/Reflection/SingleFieldAccessor.cs')
-rw-r--r-- | csharp/src/Google.Protobuf/Reflection/SingleFieldAccessor.cs | 81 |
1 files changed, 81 insertions, 0 deletions
diff --git a/csharp/src/Google.Protobuf/Reflection/SingleFieldAccessor.cs b/csharp/src/Google.Protobuf/Reflection/SingleFieldAccessor.cs new file mode 100644 index 00000000..de92fbc1 --- /dev/null +++ b/csharp/src/Google.Protobuf/Reflection/SingleFieldAccessor.cs @@ -0,0 +1,81 @@ +#region Copyright notice and license +// Protocol Buffers - Google's data interchange format +// Copyright 2015 Google Inc. All rights reserved. +// https://developers.google.com/protocol-buffers/ +// +// 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, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +#endregion + +using System; +using System.Reflection; +using Google.Protobuf.Compatibility; + +namespace Google.Protobuf.Reflection +{ + /// <summary> + /// Accessor for single fields. + /// </summary> + internal sealed class SingleFieldAccessor : FieldAccessorBase + { + // All the work here is actually done in the constructor - it creates the appropriate delegates. + // There are various cases to consider, based on the property type (message, string/bytes, or "genuine" primitive) + // and proto2 vs proto3 for non-message types, as proto3 doesn't support "full" presence detection or default + // values. + + private readonly Action<IMessage, object> setValueDelegate; + private readonly Action<IMessage> clearDelegate; + + internal SingleFieldAccessor(PropertyInfo property, FieldDescriptor descriptor) : base(property, descriptor) + { + if (!property.CanWrite) + { + throw new ArgumentException("Not all required properties/methods available"); + } + setValueDelegate = ReflectionUtil.CreateActionIMessageObject(property.GetSetMethod()); + + var clrType = property.PropertyType; + + // TODO: Validate that this is a reasonable single field? (Should be a value type, a message type, or string/ByteString.) + object defaultValue = + typeof(IMessage).IsAssignableFrom(clrType) ? null + : clrType == typeof(string) ? "" + : clrType == typeof(ByteString) ? ByteString.Empty + : Activator.CreateInstance(clrType); + clearDelegate = message => SetValue(message, defaultValue); + } + + public override void Clear(IMessage message) + { + clearDelegate(message); + } + + public override void SetValue(IMessage message, object value) + { + setValueDelegate(message, value); + } + } +} |