return map.isEmpty();
    }

    /**
     * Returns true if this set contains the specified element.
     *
     * @param o
     *            element whose presence in this set is to be tested.
     * @return true if this set contains the specified element.
     */
    @Override
    public boolean contains(final Object o) {
        return map.containsKey(o);
    }

    /**

import com.google.common.testing.RelationshipTester.Item;
import com.google.errorprone.annotations.CanIgnoreReturnValue;
import java.util.ArrayList;
import java.util.List;
import org.jspecify.annotations.NullMarked;

/**
 * Tester for {@link Equivalence} relationships between groups of objects.
 *
 * <p>To use, create a new {@link EquivalenceTester} and add equivalence groups where each group

import com.google.common.collect.Multimap;
import com.google.common.collect.testing.features.CollectionSize;
import com.google.common.collect.testing.features.MapFeature;
import org.junit.Ignore;

/**
 * Tester for {@link Multimap#containsValue}.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
@Ignore("test runners must not instantiate and run this directly, only via suites we build")

  public void testNulls() throws Exception {
    NullPointerTester tester = new NullPointerTester();
    tester.testAllPublicStaticMethods(LinkedListMultimap.class);
    tester.ignore(LinkedListMultimap.class.getMethod("get", Object.class));
    tester.ignore(LinkedListMultimap.class.getMethod("removeAll", Object.class));
    tester.testAllPublicInstanceMethods(LinkedListMultimap.create());
  }

  }

  @J2ktIncompatible
  @GwtIncompatible // NullPointerTester
  public void testNullPointers() {
    NullPointerTester tester = new NullPointerTester();
    tester.testAllPublicConstructors(MinMaxPriorityQueue.class);
    tester.testAllPublicStaticMethods(MinMaxPriorityQueue.class);
    tester.testAllPublicInstanceMethods(MinMaxPriorityQueue.<String>create());
  }

  }

  static void checkPositive(int value, String name) {
    if (value <= 0) {
      throw new IllegalArgumentException(name + " must be positive but was: " + value);
    }
  }

  /**
   * Precondition tester for {@code Iterator.remove()} that throws an exception with a consistent
   * error message.
   */
  static void checkRemove(boolean canRemove) {
    checkState(canRemove, "no calls to next() since the last call to remove()");

        assertThat(WildcardType.class.isInstance(GenericsUtil.getElementTypeOfList(t3)), is(true));
    }

    /**
     * @throws Exception
     */
    public void testSet() throws Exception {
        final Method m1 = SetType.class.getMethod("setOfString");
        final Type t1 = m1.getGenericReturnType();
        assertThat(GenericsUtil.isTypeOf(t1, Set.class), is(true));

    hasher.assertBytes(expected);
  }

  public void testShort() {
    TestHasher hasher = new TestHasher();
    hasher.putShort((short) 0x0201);
    hasher.assertBytes(new byte[] {1, 2});
  }

  public void testInt() {
    TestHasher hasher = new TestHasher();
    hasher.putInt(0x04030201);
    hasher.assertBytes(new byte[] {1, 2, 3, 4});
  }

  public void testLong() {
    TestHasher hasher = new TestHasher();

import com.google.common.collect.testing.features.CollectionSize;
import com.google.common.collect.testing.features.MapFeature;
import java.util.Iterator;
import org.junit.Ignore;

/**
 * Tester for {@code Multimap.entries}.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
@Ignore("test runners must not instantiate and run this directly, only via suites we build")

import java.util.Collections;
import java.util.Set;
import org.jspecify.annotations.Nullable;

/**
 * Encapsulates the constraints that a class under test must satisfy in order for a tester method to
 * be run against that class.
 *
 * @author George van den Driessche
 */
@GwtCompatible
public final class TesterRequirements {
  private final Set<Feature<?>> presentFeatures;