return backingIterator.hasNext();
  }

  @Override
  @ParametricNullness
  public final T next() {
    return transform(backingIterator.next());
  }

  @Override
  public final void remove() {
    backingIterator.remove();
  }

   */
  @CanIgnoreReturnValue
  public E removeFirst() {
    return remove();
  }

  /**
   * Retrieves, but does not remove, the least element of this queue, or returns {@code null} if the
   * queue is empty.
   */
  public @Nullable E peekFirst() {
    return peek();
  }

  /**
   * Removes and returns the greatest element of this queue, or returns {@code null} if the queue is
   * empty.
   */

    assertThat(map.containsKey(one)).isTrue();
    assertThat(map.containsValue(one)).isTrue();
    assertThat(map.remove(one)).isSameInstanceAs(one);
    assertThat(map).isEmpty();

    cache.getUnchecked(one);
    assertThat(map).hasSize(1);
    assertThat(map.remove(one, two)).isFalse();
    assertThat(map.remove(one, one)).isTrue();
    assertThat(map).isEmpty();

    cache.getUnchecked(one);

    assertThat(map.containsKey(one)).isTrue();
    assertThat(map.containsValue(one)).isTrue();
    assertThat(map.remove(one)).isSameInstanceAs(one);
    assertThat(map).isEmpty();

    cache.getUnchecked(one);
    assertThat(map).hasSize(1);
    assertThat(map.remove(one, two)).isFalse();
    assertThat(map.remove(one, one)).isTrue();
    assertThat(map).isEmpty();

    cache.getUnchecked(one);

          }

          @Override
          public T next() {
            return listIter.previous();
          }

          @Override
          public void remove() {
            listIter.remove();
          }
        };
  }

  static <T extends @Nullable Object> Iterator<T> cycle(Iterable<T> iterable) {
    return new Iterator<T>() {

import com.google.common.annotations.GwtCompatible;
import com.google.errorprone.annotations.DoNotCall;
import java.util.Iterator;
import org.jspecify.annotations.Nullable;

/**
 * An iterator that does not support {@link #remove}.
 *
 * <p>{@code UnmodifiableIterator} is used primarily in conjunction with implementations of {@link
 * ImmutableCollection}, such as {@link ImmutableList}. You can, however, convert an existing

    return backingIterator.hasNext();
  }

  @Override
  @ParametricNullness
  public final T next() {
    return transform(backingIterator.next());
  }

  @Override
  public final void remove() {
    backingIterator.remove();
  }

        return delegate().iterator();
      }

      @Override
      public int size() {
        return delegate().size();
      }

      @Override
      public boolean remove(Object o) {
        return delegate().remove(o);
      }

      @Override
      public void clear() {
        delegate().clear();
      }
    };
  }

  @Override
  public @Nullable Entry<K, V> firstEntry() {

            // Verify trailing slash is removed and URL is correct
            assertNotNull(url);
            assertEquals("https://fess.example.com/sso/metadata", url);
        } finally {
            // Clean up
            systemProperties.remove("saml.sp.base.url");
        }
    }

    @Test

   * Thus, calls like asMap().values().remove(someSet) are safe because they are comparing a set to
   * a collection of other sets.
   */
  @SuppressWarnings("CollectionUndefinedEquality")
  public void testValuesRemove() {
    resetContainer(mapEntry(k0(), v0()), mapEntry(k1(), v0()), mapEntry(k0(), v3()));
    assertTrue(multimap().asMap().values().remove(singleton(v0())));
    assertEquals(2, multimap().size());