docs: @javax.annotation.Nonnull
    public com.simiacryptus.util.MonitoredObject clearConstants() {
      @javax.annotation.Nonnull final HashSet<String> keys = new HashSet<>(items.keySet());
      for (final String k : keys) {
        final Object v = items.get(k);
        if (v instanceof com.simiacryptus.util.MonitoredObject) {
          ((com.simiacryptus.util.MonitoredObject) v).clearConstants();
        }
        else if (!(v instanceof Supplier) && !(v instanceof MonitoredItem)) {
          items.remove(k);
        }
      }
      return this;
    }