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

/**
 * Unit test for {@link Optional}.
 *
 * @author Kurt Alfred Kluever
 */
@ElementTypesAreNonnullByDefault
@GwtCompatible(emulated = true)
public final class OptionalTest extends TestCase {
  public void testToJavaUtil_static() {
    assertNull(Optional.toJavaUtil(null));

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

/**
 * Unit test for {@link Optional}.
 *
 * @author Kurt Alfred Kluever
 */
@ElementTypesAreNonnullByDefault
@GwtCompatible(emulated = true)
public final class OptionalTest extends TestCase {
  public void testAbsent() {
    Optional<String> optionalName = Optional.absent();