*
   * If the library is loaded in an application class loader, we try to break the cycle by loading
   * Finalizer in its own independent class loader:
   *
   * System class loader -> Application class loader -> ReferenceMap -> FinalizableReferenceQueue ->
   * etc. -> Decoupled class loader -> Finalizer
   *

   * {@code key}, simply waits for that thread to finish and returns its loaded value. Note that
   * multiple threads can concurrently load values for distinct keys.
   *
   * <p>Caches loaded by a {@link CacheLoader} will call {@link CacheLoader#load} to load new values
   * into the cache. Newly loaded values are added to the cache using {@code

      this.file = checkNotNull(file);
      this.resourceName = checkNotNull(resourceName);
      this.loader = checkNotNull(loader);
    }

    /**
     * Returns the url identifying the resource.
     *
     * <p>See {@link ClassLoader#getResource}
     *
     * @throws NoSuchElementException if the resource cannot be loaded through the class loader,
     *     despite physically existing in the class path.

   *
   * When we reference FinalizableReferenceQueue in this test, we are referencing a class that is
   * loaded by this test and that will obviously remain loaded for as long as the test is running.
   * So in order to check ClassLoader garbage collection we need to create a new ClassLoader and
   * make it load its own version of FinalizableReferenceQueue. Then we need to interact with that

		cpuNice:           "CPU nice time",
		cpuLoad1:          "CPU load average 1min",
		cpuLoad5:          "CPU load average 5min",
		cpuLoad15:         "CPU load average 15min",
		cpuLoad1Perc:      "CPU load average 1min (perentage)",
		cpuLoad5Perc:      "CPU load average 5min (percentage)",
		cpuLoad15Perc:     "CPU load average 15min (percentage)",
	}
	resourceMetricsGroups = []*MetricsGroupV2{

// metrics with a `bucket` dimension (label), use `NewBucketMetricsGroup`.
//
// The `loader` function loads metrics from the cache and the system.
func NewMetricsGroup(path collectorPath, descriptors []MetricDescriptor,
	loader MetricsLoaderFn,
) *MetricsGroup {
	mg := &MetricsGroup{
		CollectorPath: path,
		Descriptors:   descriptors,
		loader:        loader,
	}
	mg.validate()
	return mg
}

   * #loadSuccessCount}). Multiple concurrent misses for the same key will result in a single load
   * operation. This may be incremented not in conjunction with {@code missCount} if the load occurs
   * as a result of a refresh or if the cache loader returned more items than was requested. {@code
   * missCount} may also be incremented not in conjunction with this (nor {@link #loadSuccessCount})

   * #loadSuccessCount}). Multiple concurrent misses for the same key will result in a single load
   * operation. This may be incremented not in conjunction with {@code missCount} if the load occurs
   * as a result of a refresh or if the cache loader returned more items than was requested. {@code
   * missCount} may also be incremented not in conjunction with this (nor {@link #loadSuccessCount})

  /**
   * Load 8 bytes into long in a little endian manner, from the substring between position and
   * position + 8. The array must have at least 8 bytes from offset (inclusive).
   *
   * @param input the input bytes
   * @param offset the offset into the array at which to start
   * @return a long of a concatenated 8 bytes
   */
  static long load64(byte[] input, int offset) {

 * loader. That way, this class doesn't prevent the main class loader from getting garbage
 * collected, and this class can detect when the main class loader has been garbage collected and
 * stop itself.
 */
// no @ElementTypesAreNonNullByDefault for the reasons discussed above
public class Finalizer implements Runnable {