/**
 * Captures the actual type of {@code T}.
 *
 * @author Ben Yu
 */
abstract class TypeCapture<T> {

  /** Returns the captured type. */
  final Type capture() {
    Type superclass = getClass().getGenericSuperclass();
    checkArgument(superclass instanceof ParameterizedType, "%s isn't parameterized", superclass);
    return ((ParameterizedType) superclass).getActualTypeArguments()[0];
  }

 *
 * @author Ben Yu
 */
@NullUnmarked
public class TypeVisitorTest extends TestCase {

  public void testVisitNull() {
    new BaseTypeVisitor()
        .visit(((ParameterizedType) ArrayList.class.getGenericSuperclass()).getOwnerType());
  }

  public void testVisitClass() {
    assertVisited(String.class);
    new BaseTypeVisitor() {
      @Override
      void visitClass(Class<?> t) {}
    }.visit(String.class);
  }

 *
 * @author Ben Yu
 */
@NullUnmarked
public class TypeVisitorTest extends TestCase {

  public void testVisitNull() {
    new BaseTypeVisitor()
        .visit(((ParameterizedType) ArrayList.class.getGenericSuperclass()).getOwnerType());
  }

  public void testVisitClass() {
    assertVisited(String.class);
    new BaseTypeVisitor() {
      @Override
      void visitClass(Class<?> t) {}
    }.visit(String.class);
  }