* won't be cleared as long as the enum constant is referenced somewhere, and the enum constant
     * is referenced somewhere for as long as the enum class is loaded. *Maybe in theory* the enum
     * class could be unloaded after the above call to `getEnumConstants` but before we call
     * `get()`, but that is vanishingly unlikely.
     */
    return ref == null ? Optional.absent() : Optional.fromNullable(enumClass.cast(ref.get()));
  }

	Endpoint string `json:"-"`
	// Secure is true if the replication target endpoint is secure
	Secure bool `json:"-"`
}

func (sr *SRStats) update(st replStat, dID string) {
	sr.lock.Lock()
	defer sr.lock.Unlock()
	srs, ok := sr.M[dID]
	if !ok {
		srs = &SRStatus{
			XferRateLrg: newXferStats(),
			XferRateSml: newXferStats(),
		}
	}
	srs.Endpoint = st.Endpoint
	srs.Secure = st.Secure
	switch {

				//
				// - Do not consume disks which are being healed
				//
				// - Future: skip busy disks
				return
			}

			mu.Lock()
			newDisks = append(newDisks, disks[i])
			mu.Unlock()
		}()
	}
	wg.Wait()
	return newDisks
}

func (er erasureObjects) getOnlineLocalDisks() (newDisks []StorageAPI) {
	disks := er.getOnlineDisks()

        @Override
        public boolean isBlocked() {
            return false;
        }

        @Override
        public void setBlocked(boolean blocked) {}
    }

 * Prevents cascading failures by temporarily blocking requests to a failing service.
 *
 * The circuit breaker has three states:
 * - CLOSED: Normal operation, requests pass through
 * - OPEN: Service is failing, requests are blocked
 * - HALF_OPEN: Testing if service has recovered
 */
public class SmbCircuitBreaker {

    private static final Logger log = LoggerFactory.getLogger(SmbCircuitBreaker.class);

    /**
     * Circuit breaker states

		handler.PutResponse(resp)
		n++
		return nil
	})

	errFatal(err)
	t.Log("EOF.", payloads, " Roundtrips:", time.Since(start))
}

// testServerStreamResponseBlocked will test if server can handle a blocked response stream
func testServerStreamResponseBlocked(t *testing.T, local, remote *Manager) {
	defer testlogger.T.SetErrorTB(t)()
	errFatal := func(err error) {
		t.Helper()
		if err != nil {
			t.Fatal(err)

		globalHTTPStats.incS3RequestsIncoming()

		if r.Header.Get(globalObjectPerfUserMetadata) == "" {
			if val := globalServiceFreeze.Load(); val != nil {
				if unlock, ok := val.(chan struct{}); ok && unlock != nil {
					// Wait until unfrozen.
					select {
					case <-unlock:
					case <-r.Context().Done():
						// if client canceled we don't need to wait here forever.
						return
					}
				}
			}
		}

        buf.append("\"classes\":{");
        append(buf, "loaded", () -> classes.getLoadedClassCount()).append(',');
        append(buf, "total_loaded", () -> classes.getTotalLoadedClassCount()).append(',');
        append(buf, "unloaded", () -> classes.getUnloadedClassCount());
        buf.append("},");
        append(buf, "uptime", () -> jvmStats.getUptime().getMillis());
        buf.append("},");
    }

    /** Cleanup collected entries when the lock is available. */
    void tryDrainReferenceQueues() {
      if (tryLock()) {
        try {
          maybeDrainReferenceQueues();
        } finally {
          unlock();
        }
      }
    }

    @GuardedBy("this")
    void drainKeyReferenceQueue(ReferenceQueue<K> keyReferenceQueue) {
      Reference<? extends K> ref;
      int i = 0;

		ExpirationWorkersWait:  opts.ExpirationWorkersWait,
	}
}

// Update updates opts with nopts
func (opts *Config) Update(nopts Config) {
	configMu.Lock()
	defer configMu.Unlock()

	opts.ReplicationWorkersWait = nopts.ReplicationWorkersWait
	opts.KeyRotationWorkersWait = nopts.KeyRotationWorkersWait
	opts.ExpirationWorkersWait = nopts.ExpirationWorkersWait
}