Java8Module.java 文件源码

@Provides
@Singleton
private Server metricServer(final MetricRegistry metricRegistry) throws Exception {
    metricRegistry.registerAll(new GarbageCollectorMetricSet());
    metricRegistry.registerAll(new MemoryUsageGaugeSet());
    metricRegistry.registerAll(new ThreadStatesGaugeSet());

    final HealthCheckRegistry notUsed = new HealthCheckRegistry();

    AdminServletContextListener ascl =  new AdminServletContextListener() {

        @Override
        protected MetricRegistry getMetricRegistry() {
            return metricRegistry;
        }

        @Override
        protected HealthCheckRegistry getHealthCheckRegistry() {
            return notUsed;
        }
    };

    final Server server = new Server(7070);
    ServletContextHandler context = new ServletContextHandler();
    context.addEventListener(ascl);
    context.setContextPath("/");
    context.setInitParameter(MetricsServlet.DURATION_UNIT, TimeUnit.MILLISECONDS.toString());
    context.setInitParameter(MetricsServlet.RATE_UNIT, TimeUnit.SECONDS.toString());
    server.setHandler(context);
    ServletHolder holder = new ServletHolder(new AdminServlet());
    context.addServlet(holder, "/*");

    server.start();

    Runtime.getRuntime().addShutdownHook(new Thread() {
        @Override
        public void run() {
            try {
                server.stop();
            } catch (Exception e) {
                throw new AssertionError(e);
            }
        }
    });

    return server;
}