public void testOffer_supportedNotPresent() {
    assertTrue("offer(notPresent) should return true", getQueue().offer(e3()));
    expectAdded(e3());
  }

  @CollectionFeature.Require({SUPPORTS_ADD, ALLOWS_NULL_VALUES})
  public void testOffer_nullSupported() {
    assertTrue("offer(null) should return true", getQueue().offer(null));
    expectAdded((E) null);
  }

 * to the methods of the delegate. For example, overriding {@link #add} alone <b>will not</b> change
 * the behaviour of {@link #offer} which can lead to unexpected behaviour. In this case, you should
 * override {@code offer} as well, either providing your own implementation, or delegating to the
 * provided {@code standardOffer} method.
 *

  private static final class TestQueue<E> implements Queue<E> {
    private final Queue<E> delegate = Lists.newLinkedList();
    public Object mutex;

    @Override
    public boolean offer(E o) {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.offer(o);
    }

    @Override
    public @Nullable E poll() {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.poll();
    }

    @Override

 * methods of the delegate. For example, overriding {@link #add} alone <b>will not</b> change the
 * behavior of {@link #offer} which can lead to unexpected behavior. In this case, you should
 * override {@code offer} as well.
 *
 * <p><b>{@code default} method warning:</b> This class does <i>not</i> forward calls to {@code

import com.google.common.annotations.J2ktIncompatible;
import java.io.DataOutput;
import java.io.IOException;

/**
 * An extension of {@code DataOutput} for writing to in-memory byte arrays; its methods offer
 * identical functionality but do not throw {@link IOException}.
 *
 * @author Jayaprabhakar Kadarkarai
 * @since 1.0
 */
@J2ktIncompatible
@GwtIncompatible
@ElementTypesAreNonnullByDefault

 *
 * <p>The classes in this package include:
 *
 * <h2>Immutable collections</h2>
 *
 * These are collections whose contents will never change. They also offer a few additional
 * guarantees (see {@link ImmutableCollection} for details). Implementations are available for both
 * the JDK collection types and the Guava collection types (listed below).
 *
 * <h2>Collection types</h2>
 *

 * even {@code java.util.HashSet}, and places considerably less load on the garbage collector. Like
 * {@code java.util.LinkedHashSet}, it offers insertion-order iteration, with identical behavior.
 *
 * <p>This class should not be assumed to be universally superior to {@code
 * java.util.LinkedHashSet}. Generally speaking, this class reduces object allocation and memory

    for (int i = 0; i < 10; i++) {
      top.offer(i);
    }
    assertThat(top.topK()).isEmpty();
  }

  public void testNoElementsOffered() {
    TopKSelector<Integer> top = TopKSelector.least(10);
    assertThat(top.topK()).isEmpty();
  }

  public void testOfferedFewerThanK() {
    TopKSelector<Integer> top = TopKSelector.least(10);
    top.offer(3);
    top.offer(5);
    top.offer(2);

      return standardToArray(array);
    }

    @Override
    public String toString() {
      return standardToString();
    }

    @Override
    public boolean offer(T o) {
      return standardOffer(o);
    }

    @Override
    public @Nullable T peek() {
      return standardPeek();
    }

    @Override
    public @Nullable T poll() {

   * of the queue is evicted to make room.
   *
   * @return {@code true} always
   */
  @Override
  @CanIgnoreReturnValue
  public boolean offer(E e) {
    return add(e);
  }

  /**
   * Adds the given element to this queue. If the queue is currently full, the element at the head
   * of the queue is evicted to make room.
   *