diff options
Diffstat (limited to 'csharp/src/Google.Protobuf/MessageParser.cs')
-rw-r--r-- | csharp/src/Google.Protobuf/MessageParser.cs | 141 |
1 files changed, 131 insertions, 10 deletions
diff --git a/csharp/src/Google.Protobuf/MessageParser.cs b/csharp/src/Google.Protobuf/MessageParser.cs index 6a6f1017..8889638b 100644 --- a/csharp/src/Google.Protobuf/MessageParser.cs +++ b/csharp/src/Google.Protobuf/MessageParser.cs @@ -36,6 +36,109 @@ using System.IO; namespace Google.Protobuf { /// <summary> + /// A general message parser, typically used by reflection-based code as all the methods + /// return simple <see cref="IMessage"/>. + /// </summary> + public class MessageParser + { + private Func<IMessage> factory; + + internal MessageParser(Func<IMessage> factory) + { + this.factory = factory; + } + + /// <summary> + /// Creates a template instance ready for population. + /// </summary> + /// <returns>An empty message.</returns> + internal IMessage CreateTemplate() + { + return factory(); + } + + /// <summary> + /// Parses a message from a byte array. + /// </summary> + /// <param name="data">The byte array containing the message. Must not be null.</param> + /// <returns>The newly parsed message.</returns> + public IMessage ParseFrom(byte[] data) + { + ProtoPreconditions.CheckNotNull(data, "data"); + IMessage message = factory(); + message.MergeFrom(data); + return message; + } + + /// <summary> + /// Parses a message from the given byte string. + /// </summary> + /// <param name="data">The data to parse.</param> + /// <returns>The parsed message.</returns> + public IMessage ParseFrom(ByteString data) + { + ProtoPreconditions.CheckNotNull(data, "data"); + IMessage message = factory(); + message.MergeFrom(data); + return message; + } + + /// <summary> + /// Parses a message from the given stream. + /// </summary> + /// <param name="input">The stream to parse.</param> + /// <returns>The parsed message.</returns> + public IMessage ParseFrom(Stream input) + { + IMessage message = factory(); + message.MergeFrom(input); + return message; + } + + /// <summary> + /// Parses a length-delimited message from the given stream. + /// </summary> + /// <remarks> + /// The stream is expected to contain a length and then the data. Only the amount of data + /// specified by the length will be consumed. + /// </remarks> + /// <param name="input">The stream to parse.</param> + /// <returns>The parsed message.</returns> + public IMessage ParseDelimitedFrom(Stream input) + { + IMessage message = factory(); + message.MergeDelimitedFrom(input); + return message; + } + + /// <summary> + /// Parses a message from the given coded input stream. + /// </summary> + /// <param name="input">The stream to parse.</param> + /// <returns>The parsed message.</returns> + public IMessage ParseFrom(CodedInputStream input) + { + IMessage message = factory(); + message.MergeFrom(input); + return message; + } + + /// <summary> + /// Parses a message from the given JSON. + /// </summary> + /// <param name="json">The JSON to parse.</param> + /// <returns>The parsed message.</returns> + /// <exception cref="InvalidJsonException">The JSON does not comply with RFC 7159</exception> + /// <exception cref="InvalidProtocolBufferException">The JSON does not represent a Protocol Buffers message correctly</exception> + public IMessage ParseJson(string json) + { + IMessage message = factory(); + JsonParser.Default.Merge(message, json); + return message; + } + } + + /// <summary> /// A parser for a specific message type. /// </summary> /// <remarks> @@ -51,8 +154,12 @@ namespace Google.Protobuf /// </p> /// </remarks> /// <typeparam name="T">The type of message to be parsed.</typeparam> - public sealed class MessageParser<T> where T : IMessage<T> + public sealed class MessageParser<T> : MessageParser where T : IMessage<T> { + // Implementation note: all the methods here *could* just delegate up to the base class and cast the result. + // The current implementation avoids a virtual method call and a cast, which *may* be significant in some cases. + // Benchmarking work is required to measure the significance - but it's only a few lines of code in any case. + // The API wouldn't change anyway - just the implementation - so this work can be deferred. private readonly Func<T> factory; /// <summary> @@ -63,7 +170,7 @@ namespace Google.Protobuf /// to require a parameterless constructor: delegates are significantly faster to execute. /// </remarks> /// <param name="factory">Function to invoke when a new, empty message is required.</param> - public MessageParser(Func<T> factory) + public MessageParser(Func<T> factory) : base(() => factory()) { this.factory = factory; } @@ -72,7 +179,7 @@ namespace Google.Protobuf /// Creates a template instance ready for population. /// </summary> /// <returns>An empty message.</returns> - internal T CreateTemplate() + internal new T CreateTemplate() { return factory(); } @@ -82,9 +189,9 @@ namespace Google.Protobuf /// </summary> /// <param name="data">The byte array containing the message. Must not be null.</param> /// <returns>The newly parsed message.</returns> - public T ParseFrom(byte[] data) + public new T ParseFrom(byte[] data) { - Preconditions.CheckNotNull(data, "data"); + ProtoPreconditions.CheckNotNull(data, "data"); T message = factory(); message.MergeFrom(data); return message; @@ -95,9 +202,9 @@ namespace Google.Protobuf /// </summary> /// <param name="data">The data to parse.</param> /// <returns>The parsed message.</returns> - public T ParseFrom(ByteString data) + public new T ParseFrom(ByteString data) { - Preconditions.CheckNotNull(data, "data"); + ProtoPreconditions.CheckNotNull(data, "data"); T message = factory(); message.MergeFrom(data); return message; @@ -108,7 +215,7 @@ namespace Google.Protobuf /// </summary> /// <param name="input">The stream to parse.</param> /// <returns>The parsed message.</returns> - public T ParseFrom(Stream input) + public new T ParseFrom(Stream input) { T message = factory(); message.MergeFrom(input); @@ -124,7 +231,7 @@ namespace Google.Protobuf /// </remarks> /// <param name="input">The stream to parse.</param> /// <returns>The parsed message.</returns> - public T ParseDelimitedFrom(Stream input) + public new T ParseDelimitedFrom(Stream input) { T message = factory(); message.MergeDelimitedFrom(input); @@ -136,11 +243,25 @@ namespace Google.Protobuf /// </summary> /// <param name="input">The stream to parse.</param> /// <returns>The parsed message.</returns> - public T ParseFrom(CodedInputStream input) + public new T ParseFrom(CodedInputStream input) { T message = factory(); message.MergeFrom(input); return message; } + + /// <summary> + /// Parses a message from the given JSON. + /// </summary> + /// <param name="json">The JSON to parse.</param> + /// <returns>The parsed message.</returns> + /// <exception cref="InvalidJsonException">The JSON does not comply with RFC 7159</exception> + /// <exception cref="InvalidProtocolBufferException">The JSON does not represent a Protocol Buffers message correctly</exception> + public new T ParseJson(string json) + { + T message = factory(); + JsonParser.Default.Merge(message, json); + return message; + } } } |