请大虾帮忙按下列要求写一个解压缩的类

public interface ICompressor
    {
        byte[] Compress(Stream inputStream);
        byte[] Compress(byte[] buffer);
        byte[] Decompress(Stream inputStream);
        byte[] Decompress(byte[] buffer);
     }public class GZipCompressor: ICompressor
    {
        private const int BUFFER_SIZE = 256 * 1024; //256K
        private GZipStream zipStream;        public GZipCompressor()
        {
        }        public byte[] Compress(Stream stream)
        {
            MemoryStream ms = new MemoryStream();
            zipStream = new GZipStream(ms, CompressionMode.Compress);
            byte[] buffer = new byte[BUFFER_SIZE];
            int count = stream.Read(buffer, 0, buffer.Length);
            while (count > 0)
            {
                zipStream.Write(buffer, 0, count);
                count = stream.Read(buffer, 0, buffer.Length);
            }
            zipStream.Flush();
            zipStream.Close();
            byte[] compressed = ms.ToArray();
            ms.Close();
            return compressed;
        }        public byte[] Compress(byte[] buffer)
        {
            MemoryStream ms = new MemoryStream();
            zipStream = new GZipStream(ms, CompressionMode.Compress);
            zipStream.Write(buffer, 0, buffer.Length);
            zipStream.Flush();
            zipStream.Close();
            byte[] compressed = ms.ToArray();
            ms.Close();
            return compressed;
        }        public byte[] Decompress(Stream inputStream)
        {
            MemoryStream ms = new MemoryStream();
            zipStream = new GZipStream(inputStream, CompressionMode.Decompress);
            byte[] buffer = new byte[BUFFER_SIZE];
            int count = zipStream.Read(buffer, 0, buffer.Length);
            while (count > 0)
            {
                ms.Write(buffer, 0, count);
                count = zipStream.Read(buffer, 0, buffer.Length);
            }
            zipStream.Close();
            byte[] decompressed = ms.ToArray();
            ms.Close();
            return decompressed;
        }        public byte[] Decompress(byte[] buffer)
        {
            MemoryStream ms = new MemoryStream(buffer);
            return Decompress(ms);
        }
    }