Multimap<String, Integer> multimap = createMultimap();
    return multimap.asMap();
  }

  @Override
  protected Map<String, Collection<Integer>> makePopulatedMap() {
    Multimap<String, Integer> multimap = createMultimap();
    populate(multimap);
    return multimap.asMap();
  }

import org.jspecify.annotations.Nullable;

/**
 * Basic implementation of the {@link Multimap} interface. This class represents a multimap as a map
 * that associates each key with a collection of values. All methods of {@link Multimap} are
 * supported, including those specified as optional in the interface.
 *
 * <p>To implement a multimap, a subclass must define the method {@link #createCollection()}, which

    return Multimaps.transformValues(
            ArrayListMultimap.<String, Integer>create(), Functions.<Integer>identity())
        .asMap();
  }

  @Override
  protected Map<String, Collection<Integer>> makePopulatedMap() {
    ListMultimap<String, Integer> delegate = ArrayListMultimap.create();
    populate(delegate);

import org.jspecify.annotations.Nullable;

/**
 * Basic implementation of the {@link Multimap} interface. This class represents a multimap as a map
 * that associates each key with a collection of values. All methods of {@link Multimap} are
 * supported, including those specified as optional in the interface.
 *
 * <p>To implement a multimap, a subclass must define the method {@link #createCollection()}, which

  // Comparison and hashing

  @Override
  public boolean equals(@Nullable Object object) {
    return Multimaps.equalsImpl(this, object);
  }

  /**
   * Returns the hash code for this multimap.
   *
   * <p>The hash code of a multimap is defined as the hash code of the map view, as returned by
   * {@link Multimap#asMap}.
   *
   * @see Map#hashCode
   */
  @Override
  public int hashCode() {

  // Comparison and hashing

  @Override
  public boolean equals(@Nullable Object object) {
    return Multimaps.equalsImpl(this, object);
  }

  /**
   * Returns the hash code for this multimap.
   *
   * <p>The hash code of a multimap is defined as the hash code of the map view, as returned by
   * {@link Multimap#asMap}.
   *
   * @see Map#hashCode
   */
  @Override
  public int hashCode() {

   * assertThat(colorForName).containsEntry("red", red);
   * }
   *
   * <p>If your index may associate multiple values with each key, use {@link
   * Multimaps#index(Iterable, Function) Multimaps.index}.
   *
   * <p><b>Note:</b> on Java 8+, it is usually better to use streams. For example:
   *
   * {@snippet :
   * import static com.google.common.collect.ImmutableMap.toImmutableMap;

   * assertThat(colorForName).containsEntry("red", red);
   * }
   *
   * <p>If your index may associate multiple values with each key, use {@link
   * Multimaps#index(Iterable, Function) Multimaps.index}.
   *
   * <p><b>Note:</b> on Java 8+, it is usually better to use streams. For example:
   *
   * {@snippet :
   * import static com.google.common.collect.ImmutableMap.toImmutableMap;

import com.google.common.collect.ListMultimap;
import com.google.common.collect.MapDifference;
import com.google.common.collect.Maps;
import com.google.common.collect.Multimap;
import com.google.common.collect.Multimaps;
import com.google.common.collect.Multiset;
import com.google.common.collect.Ordering;
import com.google.common.collect.PeekingIterator;
import com.google.common.collect.Range;

    multimap.put("foo", -1);
    multimap.put(null, null);
    multimap.put("bar", 1);
    multimap.put("foo", 2);
    multimap.put(null, 0);
    multimap.put("bar", 2);
    multimap.put("bar", null);
    multimap.put("foo", null);
    multimap.put("foo", 4);
    multimap.put(null, -1);
    multimap.put("bar", 3);
    multimap.put("bar", 1);
    multimap.put("foo", 1);

    assertThat(multimap.toString())