Pull new version of protobuf sources.

third_party/protobuf/csharp/src/Google.Protobuf/MessageParser.cs

+#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.IO;
+
+namespace Google.Protobuf
+{
+    /// <summary>
+    /// A parser for a specific message type.
+    /// </summary>
+    /// <remarks>
+    /// <p>
+    /// This delegates most behavior to the
+    /// <see cref="IMessage.MergeFrom"/> implementation within the original type, but
+    /// provides convenient overloads to parse from a variety of sources.
+    /// </p>
+    /// <p>
+    /// Most applications will never need to create their own instances of this type;
+    /// instead, use the static <c>Parser</c> property of a generated message type to obtain a
+    /// parser for that type.
+    /// </p>
+    /// </remarks>
+    /// <typeparam name="T">The type of message to be parsed.</typeparam>
+    public sealed class MessageParser<T> where T : IMessage<T>
+    {
+        private readonly Func<T> factory; 
+
+        /// <summary>
+        /// Creates a new parser.
+        /// </summary>
+        /// <remarks>
+        /// The factory method is effectively an optimization over using a generic constraint
+        /// 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)
+        {
+            this.factory = factory;
+        }
+
+        /// <summary>
+        /// Creates a template instance ready for population.
+        /// </summary>
+        /// <returns>An empty message.</returns>
+        internal T 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 T ParseFrom(byte[] data)
+        {
+            Preconditions.CheckNotNull(data, "data");
+            T 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 T ParseFrom(ByteString data)
+        {
+            Preconditions.CheckNotNull(data, "data");
+            T 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 T ParseFrom(Stream input)
+        {
+            T 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 T ParseDelimitedFrom(Stream input)
+        {
+            T 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 T ParseFrom(CodedInputStream input)
+        {
+            T message = factory();
+            message.MergeFrom(input);
+            return message;
+        }
+    }
+}