&& builder.getValueStrength() == Strength.WEAK) {
      return new MapMakerInternalMap<>(builder, StrongKeyWeakValueEntry.Helper.instance());
    }
    if (builder.getKeyStrength() == Strength.WEAK
        && builder.getValueStrength() == Strength.STRONG) {
      return new MapMakerInternalMap<>(builder, WeakKeyStrongValueEntry.Helper.instance());
    }
    if (builder.getKeyStrength() == Strength.WEAK && builder.getValueStrength() == Strength.WEAK) {

   *   <li>clearing weak references to unreachable referents
   *   <li>enqueuing weak references to unreachable referents in their reference queue
   * </ul>
   */
  @DoNotMock("Implement with a lambda")
  public interface FinalizationPredicate {
    boolean isDone();
  }

  /**
   * Waits until the given weak reference is cleared, invoking the garbage collector as necessary to

      this.strong = true;
      return this;
    }

    /**
     * Instructs the {@link InternerBuilder} to build a weak interner.
     *
     * @see Interners#newWeakInterner()
     */
    @CanIgnoreReturnValue
    @GwtIncompatible // java.lang.ref.WeakReference
    public InternerBuilder weak() {
      this.strong = false;
      return this;
    }

    /**

  }

  public void testWeak_builder() {
    int concurrencyLevel = 42;
    Interner<Object> interner =
        Interners.newBuilder().weak().concurrencyLevel(concurrencyLevel).build();
    InternerImpl<Object> internerImpl = (InternerImpl<Object>) interner;
    assertEquals(Strength.WEAK, internerImpl.map.keyStrength());
    assertEquals(concurrencyLevel, internerImpl.map.concurrencyLevel);
  }

import com.google.common.annotations.GwtCompatible;
import com.google.common.annotations.GwtIncompatible;
import com.google.common.collect.Multiset.Entry;
import com.google.j2objc.annotations.Weak;
import java.util.Comparator;
import java.util.Iterator;
import java.util.NavigableSet;
import java.util.NoSuchElementException;
import java.util.SortedSet;
import org.jspecify.annotations.Nullable;

/**

import com.google.common.annotations.J2ktIncompatible;
import java.lang.ref.ReferenceQueue;
import java.lang.ref.WeakReference;
import org.jspecify.annotations.Nullable;

/**
 * Weak reference with a {@code finalizeReferent()} method which a background thread invokes after
 * the garbage collector reclaims the referent. This is a simpler alternative to using a {@link
 * ReferenceQueue}.
 *
 * @author Bob Lee

import com.google.common.annotations.J2ktIncompatible;
import java.lang.ref.ReferenceQueue;
import java.lang.ref.WeakReference;
import org.jspecify.annotations.Nullable;

/**
 * Weak reference with a {@code finalizeReferent()} method which a background thread invokes after
 * the garbage collector reclaims the referent. This is a simpler alternative to using a {@link
 * ReferenceQueue}.
 *
 * @author Bob Lee

    // Using @Weak is necessary to avoid retain-cycles between Node instances on iOS,
    // which would cause memory leaks when non-empty HashBiMap with cyclic Node
    // instances is deallocated.
    @Nullable Node<K, V> nextInKToVBucket;
    @Weak @Nullable Node<K, V> nextInVToKBucket;

    @Weak @Nullable Node<K, V> nextInKeyInsertionOrder;

import static com.google.common.collect.Maps.valuePredicateOnEntries;

import com.google.common.annotations.GwtCompatible;
import com.google.common.base.Predicate;
import com.google.j2objc.annotations.Weak;
import java.util.AbstractCollection;
import java.util.Collection;
import java.util.Iterator;
import java.util.Map.Entry;
import java.util.Objects;
import org.jspecify.annotations.Nullable;

/**

  }

  public void testWeak_builder() {
    int concurrencyLevel = 42;
    Interner<Object> interner =
        Interners.newBuilder().weak().concurrencyLevel(concurrencyLevel).build();
    InternerImpl<Object> internerImpl = (InternerImpl<Object>) interner;
    assertEquals(Strength.WEAK, internerImpl.map.keyStrength());
    assertEquals(concurrencyLevel, internerImpl.map.concurrencyLevel);
  }