Embedded Jetty monitoring

[Moses Gone]

I have an embedded jetty application. I intent to monitor  threads, which threads are running(by Id) , which are pending/exited with error and which ones have completed. In the end I want to push these stats to a web client as json string (might use Graphite ...but not decided on it yet)

I have just stumbled on Metrics, and I think I it could do what I want. The problem is I seem not able to Instrument my Jetty properly(am using V3.0.0BETA2). In the main class this is what am doing:

       Server server = new Server(Integer.valueOf(webPort));

    

        ServletContextHandler context = new ServletContextHandler(ServletContextHandler.SESSIONS);

        context.setAttribute("com.yammer.metrics.servlets.AdminServlet.registry", metrics);

        context.setContextPath("/");

        context.addServlet(TestServlet.class, "/test");

        context.addServlet(AdminServlet.class, "/threads");

        HandlerCollection handlers = new HandlerCollection();

       

        handlers.setHandlers(new Handler[]{context});

        server.setHandler(handlers);

On the servlet:

    final LoggerContext factory = (LoggerContext) LoggerFactory.getILoggerFactory();

    final Logger root = factory.getLogger(Logger.ROOT_LOGGER_NAME);

    MetricRegistry metrics;

   

    @Override

    public void init() throws ServletException {

        super.init();

        metrics = metricRegistry(this.getServletContext());

    }

    @Override

    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        SecureRandom random = new SecureRandom();

        byte bytes[] = new byte[20];

        random.nextBytes(bytes);

        System.out.println(req.getSession().getId() + " :Waiting..." + UUID.nameUUIDFromBytes(bytes));

        req.getRequestDispatcher("./src/webapp/index.html").forward(req, resp);

    }

  public MetricRegistry metricRegistry(ServletContext servletContext) {

  MetricRegistry metrics = new MetricRegistry();

// healthChecks.register("java", new ThreadDeadlockHealthCheck());

        metrics.registerAll(new GarbageCollectorMetricSet());

        metrics.registerAll(new JvmAttributeGaugeSet());

        metrics.registerAll(new MemoryUsageGaugeSet());

        metrics.registerAll(new ThreadStatesGaugeSet());

        LoggerContext loggerContext = (LoggerContext) LoggerFactory.getILoggerFactory();

        ch.qos.logback.classic.Logger rootLogger = loggerContext.getLogger(Logger.ROOT_LOGGER_NAME);

        ConsoleReporter reporter2 = ConsoleReporter.forRegistry(metrics)

                .convertRatesTo(TimeUnit.SECONDS)

                .convertDurationsTo(TimeUnit.MILLISECONDS)

                .build();

        reporter2.start(1, TimeUnit.MINUTES);

//        final Slf4jReporter reporter = Slf4jReporter.forRegistry(metrics)

//                .outputTo(LoggerFactory.getLogger(AdminServlet.class)).build();

//        reporter.start(10, TimeUnit.SECONDS);

        return metrics;

    }

This is obviously not working, as I keep getting this error:

javax.servlet.ServletException: Couldn't find a HealthCheckRegistry instance.

at com.codahale.metrics.servlets.HealthCheckServlet.init(HealthCheckServlet.java:37) ~[metrics-servlets-3.0.0-BETA2.jar:na]

at com.codahale.metrics.servlets.AdminServlet.init(AdminServlet.java:49) ~[metrics-servlets-3.0.0-BETA2.jar:na]