private void writeResponse(ChannelHandlerContext ctx, HttpRequest request, ByteBuf buf, CharSequence contentType, CharSequence contentLength) {
// Decide whether to close the connection or not.
boolean keepAlive = HttpHeaders.isKeepAlive(request);
// Build the response object.
FullHttpResponse response = new DefaultFullHttpResponse(HttpVersion.HTTP_1_1, HttpResponseStatus.OK, buf, false);
HttpHeaders headers = response.headers();
headers.set(CONTENT_TYPE_ENTITY, contentType);
headers.set(SERVER_ENTITY, SERVER_NAME);
headers.set(DATE_ENTITY, date);
headers.set(CONTENT_LENGTH_ENTITY, contentLength);