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.util.logging.Level;
import java.util.logging.Logger;

/**
 * A {@code TearDownStack} contains a stack of {@link TearDown} instances.
 *
 * <p>This class is thread-safe.
 *
 * @author Kevin Bourrillion
 * @since 10.0
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public class TearDownStack implements TearDownAccepter {

 * generally be avoided. Prefer {@link Interners#newWeakInterner} or another {@code Interner}
 * implementation even for {@code String} interning.
 *
 * @author Kevin Bourrillion
 * @since 3.0
 */
@DoNotMock("Use Interners.new*Interner")
@J2ktIncompatible
@GwtIncompatible
@ElementTypesAreNonnullByDefault
public interface Interner<E> {
  /**

import com.google.common.annotations.J2ktIncompatible;
import com.google.common.testing.NullPointerTester;
import java.util.Set;
import junit.framework.TestCase;

/**
 * Unit test for {@link Primitives}.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible(emulated = true)
public class PrimitivesTest extends TestCase {
  public void testIsWrapperType() {
    assertThat(Primitives.isWrapperType(Void.class)).isTrue();

 * default implementations. When those implementations invoke methods, they invoke methods on the
 * {@code ForwardingIterator}.
 *
 * @author Kevin Bourrillion
 * @since 2.0
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public abstract class ForwardingIterator<T extends @Nullable Object> extends ForwardingObject
    implements Iterator<T> {

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 com.google.common.testing.NullPointerTester;
import java.lang.ref.WeakReference;
import junit.framework.TestCase;

/**
 * Unit test for {@link Interners}.
 *
 * @author Kevin Bourrillion
 */
public class InternersTest extends TestCase {

  public void testStrong_simplistic() {
    String canonical = "a";
    String not = new String("a");