int j = findNextJ();
      if (j == -1) {
        nextPermutation = null;
        return;
      }
      /*
       * requireNonNull is safe because we don't clear nextPermutation until we're done calling this
       * method.
       */
      requireNonNull(nextPermutation);

      int l = findNextL(j);
      Collections.swap(nextPermutation, j, l);
      int n = nextPermutation.size();

  private static <N, V> GraphConnections<N, V> connectionsOf(ValueGraph<N, V> graph, N node) {
    Function<N, V> successorNodeToValueFn =
        (N successorNode) ->
            // requireNonNull is safe because the endpoint pair comes from the graph.
            requireNonNull(graph.edgeValueOrDefault(node, successorNode, null));
    return graph.isDirected()
        ? DirectedGraphConnections.ofImmutable(

 * the License.
 */

package com.google.common.reflect;

import static com.google.common.base.Preconditions.checkNotNull;
import static java.util.Objects.requireNonNull;

import com.google.common.collect.FluentIterable;
import com.google.common.collect.ImmutableList;
import java.lang.annotation.Annotation;
import java.lang.reflect.AnnotatedElement;

        // ## Assert ##
        assertEquals(before, after);
    }

    private long countTmpFiles() {
        return Arrays.stream(Objects.requireNonNull(Curl.tmpDir.listFiles())).map(File::getName)
                .filter(s -> s.startsWith(PREFIX) && s.endsWith(SUFFIX)).count();
    }

   * CompactHashMap.
   */

  private Object requireTable() {
    return requireNonNull(table);
  }

  private int[] requireEntries() {
    return requireNonNull(entries);
  }

  private @Nullable Object[] requireElements() {
    return requireNonNull(elements);
  }

  @SuppressWarnings("unchecked")
  private E element(int i) {
    return (E) requireElements()[i];

    IdentityHashMap<Entry<K, V>, Boolean> duplicates = null;
    int dupCount = 0;
    for (int entryIndex = n - 1; entryIndex >= 0; entryIndex--) {
      // requireNonNull is safe because the first `n` elements have been filled in.
      Entry<K, V> entry = requireNonNull(entryArray[entryIndex]);
      K key = entry.getKey();
      V value = entry.getValue();
      checkEntryNotNull(key, value);

import org.eclipse.aether.transfer.TransferEvent;
import org.eclipse.aether.transfer.TransferListener;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import static java.util.Objects.requireNonNull;

/**
 * A {@link TransferListener} implementation that wraps another delegate {@link TransferListener} but makes it run

  private void readObject(ObjectInputStream stream) throws IOException, ClassNotFoundException {
    stream.defaultReadObject();
    keyComparator = requireNonNull((Comparator<? super K>) stream.readObject());
    valueComparator = requireNonNull((Comparator<? super V>) stream.readObject());
    setMap(new TreeMap<K, Collection<V>>(keyComparator));
    Serialization.populateMultimap(this, stream);
  }

 * limitations under the License.
 */

package com.google.common.util.concurrent;

import static com.google.common.base.Preconditions.checkNotNull;
import static java.util.Objects.requireNonNull;

import com.google.common.annotations.GwtCompatible;
import com.google.common.annotations.J2ktIncompatible;
import com.google.errorprone.annotations.CanIgnoreReturnValue;

    public static class Holder {
        private volatile boolean set;
        private volatile Model model;

        Holder() {}

        Holder(Model model) {
            this.model = Objects.requireNonNull(model);
            this.set = true;
        }

        public static Model deref(Holder holder) {
            return holder != null ? holder.get() : null;
        }

        public Model get() {