ByteBufferOutputStream.cs

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using System.Collections.Generic;
using System.IO;
//using System.Linq;

namespace Avro.IO
{
    public class ByteBufferOutputStream : OutputStream
    {
        public const int BUFFER_SIZE = 8192;

        public ByteBufferOutputStream()
        {
            Reset();
        }

        private void Reset()
        {
            _buffers = new List<MemoryStream> {CreateBuffer()};
        }

        private List<MemoryStream> _buffers;

        private static MemoryStream CreateBuffer()
        {
            return new MemoryStream(new byte[BUFFER_SIZE], 0, BUFFER_SIZE, true, true);
        }

        public void Prepend(List<MemoryStream> lists)
        {
            foreach (var stream in lists)
            {
                stream.Position = stream.Length;
            }

            _buffers.InsertRange(0, lists);
        }

        public void Append(List<MemoryStream> lists)
        {
            foreach (var stream in lists)
            {
                stream.Position = stream.Length;
            }

            _buffers.AddRange(lists);
        }

        public override void Write(byte[] b, int off, int len)
        {
            var buffer = _buffers[_buffers.Count -1];
            var remaining = (int) (buffer.Length - buffer.Position);
            while (len > remaining)
            {
                buffer.Write(b, off, remaining);
                len -= remaining;
                off += remaining;

                buffer = CreateBuffer();
                _buffers.Add(buffer);

                remaining = (int) buffer.Length;
            }

            buffer.Write(b, off, len);
        }

        public List<MemoryStream> GetBufferList()
        {
            List<MemoryStream> result = _buffers;
            
            Reset();

            foreach (MemoryStream b in result)
            {
                // Flip()
                b.SetLength(b.Position);
                b.Position = 0;
            }

            return result;
        }

        public override long Length
        {
            get
            {
                long sum = 0;
                foreach (var buffer in _buffers)
                {
                    sum += buffer.Length;
                }

                return sum;
            }
        }

        public override void Flush()
        {
        }
    }
}