@Override
    public boolean isReady() {
        if (response == null) {
            return false;
        }
        try {
            return response.getOutputStream().isReady();
        } catch (IOException e) {
            log.error("got exception when check if  the output stream is ready", e);
        }
        return false;
    }
Wrapper output stream
When writing character data, write the data into the output stream of OutputStream and HttpServletResponse object at the same time.
inlong-manager/manager-web/src/main/java/org/apache/inlong/manager/web/trace/WrapperOutputStream.java