LoggingFilter_Part9.java

private static ContentCachingRequestWrapper wrapRequest(HttpServletRequest httpServletRequest) {
        if (httpServletRequest instanceof ContentCachingRequestWrapper) {
            return (ContentCachingRequestWrapper) httpServletRequest;
        } else {
            return new ContentCachingRequestWrapper(httpServletRequest);
        }
    }

    private static ContentCachingResponseWrapper wrapResponse(HttpServletResponse httpServletResponse) {
        if (httpServletResponse instanceof ContentCachingResponseWrapper) {
            return (ContentCachingResponseWrapper) httpServletResponse;
        } else {
            return new ContentCachingResponseWrapper(httpServletResponse);
        }
    }