import java.util.Collection;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Creates collections, containing sample elements, to be tested.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public interface TestCollectionGenerator<E extends @Nullable Object>

import com.google.common.annotations.GwtCompatible;
import java.util.Set;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Creates sets, containing sample elements, to be tested.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public interface TestSetGenerator<E extends @Nullable Object> extends TestCollectionGenerator<E> {
  @Override
  Set<E> create(Object... elements);

import com.google.common.collect.testing.SampleElements.Colliders;
import java.util.List;

/**
 * A generator using sample elements whose hash codes all collide badly.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public abstract class TestCollidingSetGenerator implements TestSetGenerator<Object> {
  @Override
  public SampleElements<Object> samples() {

import com.google.common.annotations.GwtCompatible;
import com.google.common.collect.testing.SampleElements.Strings;
import java.util.List;

/**
 * TODO: javadoc.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public abstract class TestStringListGenerator implements TestListGenerator<String> {
  @Override
  public SampleElements<String> samples() {

import java.io.ObjectOutputStream;
import java.util.HashMap;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Multiset implementation backed by a {@link HashMap}.
 *
 * @author Kevin Bourrillion
 * @author Jared Levy
 * @since 2.0
 */
@GwtCompatible(serializable = true, emulated = true)
@ElementTypesAreNonnullByDefault

import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Implementation of {@link ImmutableSet} with two or more elements.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible(serializable = true, emulated = true)
@SuppressWarnings("serial") // uses writeReplace(), not default serialization
@ElementTypesAreNonnullByDefault

import junit.framework.Test;
import junit.framework.TestCase;
import junit.framework.TestSuite;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Unit test for {@link AbstractMultiset}.
 *
 * @author Kevin Bourrillion
 * @author Louis Wasserman
 */
@SuppressWarnings("serial") // No serialization is used in this test
@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault

import junit.framework.Test;
import junit.framework.TestCase;
import junit.framework.TestSuite;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Unit test for {@link AbstractMultiset}.
 *
 * @author Kevin Bourrillion
 * @author Louis Wasserman
 */
@SuppressWarnings("serial") // No serialization is used in this test
@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault

 * }</pre>
 *
 * <p><b>Note</b>: It is necessary to use {@code IteratorTester.KnownOrder} as shown above, rather
 * than {@code KnownOrder} directly, because otherwise the code cannot be compiled.
 *
 * @author Kevin Bourrillion
 * @author Chris Povirk
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public abstract class IteratorTester<E extends @Nullable Object>
    extends AbstractIteratorTester<E, Iterator<E>> {
  /**

import java.util.NoSuchElementException;
import junit.framework.TestCase;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Unit test for {@code AbstractIterator}.
 *
 * @author Kevin Bourrillion
 */
@SuppressWarnings("serial") // No serialization is used in this test
@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault
public class AbstractIteratorTest extends TestCase {