emptyIterator.remove();
    }

    /**
     * Test method for
     * {@link org.codelibs.core.collection.EmptyIterator#hasNext()}.
     */
    @Test
    public void testHasNext() {
        final EmptyIterator<String> emptyIterator = new EmptyIterator<String>();
        assertThat(emptyIterator.hasNext(), is(false));
    }

    /**
     * Test method for {@link org.codelibs.core.collection.EmptyIterator#next()}.
     */

import com.google.caliper.api.SkipThisScenarioException;
import com.google.common.util.concurrent.AbstractFutureBenchmarks.Facade;
import com.google.common.util.concurrent.AbstractFutureBenchmarks.Impl;
import java.util.HashSet;
import java.util.Set;
import java.util.concurrent.Executor;
import org.jspecify.annotations.NullUnmarked;

/** Measures the size of AbstractFuture implementations. */
@NullUnmarked

                        // advance res2
                        if (i2.hasNext()) {
                            res2 = i2.next();
                        } else {
                            done = true;
                        }
                    } else {
                        // advance res1
                        if (i1.hasNext()) {
                            res1 = i1.next();
                        } else {

                0L, 0L);
    }

    /**
     * {@inheritDoc}
     *
     * @see java.util.Iterator#hasNext()
     */
    @Override
    public boolean hasNext() {
        return this.next != null;
    }

    /**
     * {@inheritDoc}
     *
     * @see java.util.Iterator#next()
     */
    @Override

    /**
     * Creates and returns a new instance of {@link HashSet}.
     *
     * @param <E> the element type of {@link HashSet}
     * @return a new instance of {@link HashSet}
     * @see HashSet#HashSet()
     */
    public static <E> HashSet<E> newHashSet() {
        return new HashSet<>();
    }

    /**
     * Creates and returns a new instance of {@link HashSet}.
     *

import java.io.ObjectInputStream;
import java.io.Serializable;
import java.util.AbstractCollection;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Spliterator;
import java.util.Spliterators;
import org.jspecify.annotations.Nullable;

/**

  }

  /**
   * Implementation for the EntryIterator, which is used to build Key and Value iterators.
   *
   * <p>Expiration is only checked on hasNext(), so as to ensure that a next() call never returns
   * null when hasNext() has already been called.
   */
  private final class EntryIterator implements Iterator<Entry<K, V>> {
    Iterator<Entry<K, Timestamped<V>>> iterator;

      stack.addLast(singletonIterator(checkNotNull(root)));
    }

    @Override
    public boolean hasNext() {
      return !stack.isEmpty();
    }

    @Override
    public T next() {
      Iterator<T> itr = stack.getLast(); // throws NSEE if empty
      T result = checkNotNull(itr.next());
      if (!itr.hasNext()) {
        stack.removeLast();
      }
      Iterator<T> childItr = children(result).iterator();

 * under the License.
 */
package org.apache.maven.artifact.metadata;

import javax.inject.Inject;
import javax.inject.Named;
import javax.inject.Singleton;

import java.util.HashSet;
import java.util.List;
import java.util.Set;

import org.apache.maven.artifact.Artifact;
import org.apache.maven.artifact.factory.ArtifactFactory;
import org.apache.maven.artifact.repository.ArtifactRepository;

        list.add("aaa");
        list.add("bbb");
        list.add("ccc");

        final IndexedIterator<String> it = new IndexedIterator<String>(list.iterator());

        assertThat(it.hasNext(), is(true));

        final Indexed<String> indexed1 = it.next();
        assertThat(indexed1.getIndex(), is(0));
        assertThat(indexed1.getElement(), is("aaa"));

        final Indexed<String> indexed2 = it.next();