* NodeProblemDetector is a DaemonSet running on each node, monitoring node health and reporting node problems as NodeCondition and Event. Currently it already supports kernel log monitoring, and will support more problem detection in the future. It is enabled by default on gce now.

   *
   * @since 33.2.0 (available since 21.0 in guava-jre)
   */
  @SuppressWarnings("Java7ApiChecker")
  @IgnoreJRERequirement // Users will use this only if they're already using streams.
  public static <E extends Enum<E>> Collector<E, ?, ImmutableSet<E>> toImmutableEnumSet() {
    return CollectCollectors.toImmutableEnumSet();
  }

  /**

    private boolean sourceLevelSet = false;

    public void setSourceLevel(String sourceLevel) {
        if (sourceLevelSet) {
            throw new IllegalStateException("Cannot reset sourceLevel attribute; it is already set to: " + sourceLevel);
        } else if (!(USER_LEVEL.equals(sourceLevel) || PROJECT_LEVEL.equals(sourceLevel)  || GLOBAL_LEVEL.equals(sourceLevel))) {

            System.setErr(new LoggingOutputStream(s -> stderr.warn("[stderr] " + s)).printStream());
            // no need to set them back, this is already handled by MessageUtils.systemUninstall() above
        }
    }

    protected Consumer<String> determineWriter(C context) {
        if (context.writer == null) {

      return array;
    }
    Method emptyGenerate = EMPTY_GENERATORS.get(rawType);
    if (emptyGenerate != null) {
      if (emptyInstanceGenerated.containsKey(type.getType())) {
        // empty instance already generated
        if (emptyInstanceGenerated.get(type.getType()).intValue() == freshness.get()) {
          // same freshness, generate again.
          return invokeGeneratorMethod(emptyGenerate);
        } else {

     * the entry that was inserted first will be first in the built map's iteration order.
     *
     * @throws IllegalStateException if this method was already called
     * @since 19.0
     */
    @CanIgnoreReturnValue
    @Override
    public Builder<K, V> orderEntriesByValue(Comparator<? super V> valueComparator) {
      super.orderEntriesByValue(valueComparator);

		if !containerStatus.Ready {
			fmt.Fprintf(writer, "WARNING: Pod %s Container %s NOT READY\n", kname(pod.ObjectMeta), containerStatus.Name)
		}
	}
	for _, containerStatus := range pod.Status.InitContainerStatuses {
		if !containerStatus.Ready {
			fmt.Fprintf(writer, "WARNING: Pod %s Init Container %s NOT READY\n", kname(pod.ObjectMeta), containerStatus.Name)
		}
	}

* Fixes an issue where Portworx volumes cannot be mounted if 9001 port is already in use on the host and users remap 9001 to another port. ([#70392](https://github.com/kubernetes/kubernetes/pull/70392), [@harsh-px](https://github.com/harsh-px))

    * To avoid that negative effect only use per pod metrics from pods that are:
    * - ready (so metrics about them should be valid), or
    * - unready but creation and last readiness change timestamps are apart more than 10s (pods that have formerly been ready and so metrics are in at least some cases (pod becoming unready because of overload) very useful).

   *
   * <p>Calling {@code setDistinctValues(type, v1, v2)} also sets the default value for {@code type}
   * that's used for {@link #testNulls}.
   *
   * <p>Only necessary for types where {@link ClassSanityTester} doesn't already know how to create
   * distinct values.
   *
   * @return this tester instance
   * @since 17.0
   */
  @CanIgnoreReturnValue