* @return true if the crawling should continue, false otherwise.
     */
    protected boolean isContinue(final int tcCount) {
        if (!crawlerContainer.available()) {
            // system shutdown
            return false;
        }

        boolean isContinue = false;
        if (tcCount < crawlerContext.maxThreadCheckCount) {
            final long maxAccessCount = crawlerContext.getMaxAccessCount();

      startUpCalled = true;
      assertEquals(State.STARTING, state());
      if (startUpException != null) {
        throw startUpException;
      }
    }

    @Override
    protected void shutDown() throws Exception {
      assertTrue(startUpCalled);
      assertFalse(shutDownCalled);
      shutDownCalled = true;
      if (shutDownException != null) {
        throw shutDownException;
      }
    }

      startUpCalled = true;
      assertEquals(State.STARTING, state());
      if (startUpException != null) {
        throw startUpException;
      }
    }

    @Override
    protected void shutDown() throws Exception {
      assertTrue(startUpCalled);
      assertFalse(shutDownCalled);
      shutDownCalled = true;
      if (shutDownException != null) {
        throw shutDownException;
      }
    }

}

// ObjectLayer implements primitives for object API layer.
type ObjectLayer interface {
	// Locking operations on object.
	NewNSLock(bucket string, objects ...string) RWLocker

	// Storage operations.
	Shutdown(context.Context) error
	NSScanner(ctx context.Context, updates chan<- DataUsageInfo, wantCycle uint32, scanMode madmin.HealScanMode) error
	BackendInfo() madmin.BackendInfo

                });
    }

    /**
     * Cleanup method called when the helper is being destroyed.
     * Logs cache statistics and processes any remaining statistics
     * objects in the cache before shutdown.
     */
    @PreDestroy
    public void destroy() {
        if (logger.isDebugEnabled()) {
            logger.debug("cache stats: {}", statsCache.stats());
        }

pkg net/http/httputil, type ReverseProxy struct, ModifyResponse func(*http.Response) error
pkg net/http, method (*Server) Close() error
pkg net/http, method (*Server) Shutdown(context.Context) error
pkg net/http, type Pusher interface { Push }
pkg net/http, type Pusher interface, Push(string, *PushOptions) error
pkg net/http, type PushOptions struct

        if (executorService != null) {
            try {
                executorService.shutdown();
                executorService.awaitTermination(60, TimeUnit.SECONDS);
            } catch (final InterruptedException e) {
                if (logger.isDebugEnabled()) {
                    logger.debug("Executor shutdown interrupted", e);
                }
            } finally {
                executorService.shutdownNow();

    ) -> None:
        """
        Add an event handler function for startup or shutdown.

        This method is kept for backward compatibility after Starlette removed
        support for on_startup/on_shutdown handlers.

        Ref: https://github.com/Kludex/starlette/pull/3117
        """
        assert event_type in ("startup", "shutdown")
        if event_type == "startup":
            self.on_startup.append(func)

## Version 3.4.2

_2016-11-03_

 *  Fix: Recover gracefully when an HTTP/2 connection is shutdown. We had a
    bug where shutdown HTTP/2 connections were considered usable. This caused
    infinite loops when calls attempted to recover.


## Version 3.4.1

_2016-07-10_

 *  **Fix a major bug in encoding HTTP headers.** In 3.4.0 and 3.4.0-RC1 OkHttp

    // Cause acceptConnections() to break out.
    serverSocket.closeQuietly()

    // Await shutdown.
    for (queue in taskRunner.activeQueues()) {
      if (!queue.idleLatch().await(5, TimeUnit.SECONDS)) {
        throw AssertionError("Gave up waiting for queue to shut down")
      }
    }
    taskRunnerBackend.shutdown()
  }

  private fun serveConnection(
    connectionIndex: Int,
    raw: Socket,