public HttpRequest bufferSize(final int size) {
    if (size < 1)
      throw new IllegalArgumentException("Size must be greater than zero");
    bufferSize = size;
    return this;
  }
Set the size used when buffering and copying between streams
<p>
This size is also used for send and receive buffers created for both char
and byte arrays
<p>
The default buffer size is 8,192 bytes

@param size
@return this request
lib/src/main/java/com/github/kevinsawicki/http/HttpRequest.java