* {@code default} methods were introduced</a>. For newer methods, like {@code forEach}, it inherits
 * their default implementations. When those implementations invoke methods, they invoke methods on
 * the {@code ForwardingConcurrentMap}.
 *
 * @author Charles Fry
 * @since 2.0
 */
@GwtCompatible
public abstract class ForwardingConcurrentMap<K, V> extends ForwardingMap<K, V>

        }
    }

    // Helper method to invoke protected method using reflection
    private ClassificationMeta invokeMethod(Object obj, String methodName, String param) {
        try {
            java.lang.reflect.Method method = obj.getClass().getDeclaredMethod(methodName, String.class);
            method.setAccessible(true);
            return (ClassificationMeta) method.invoke(obj, param);
        } catch (Exception e) {

      checkArgumentMethod.invoke(null /* static method */, getParametersForSignature(true, sig));

      Object[] failingParams = getParametersForSignature(false, sig);
      InvocationTargetException ite =
          assertThrows(
              InvocationTargetException.class,
              () -> checkArgumentMethod.invoke(null /* static method */, failingParams));

      checkArgumentMethod.invoke(null /* static method */, getParametersForSignature(true, sig));

      Object[] failingParams = getParametersForSignature(false, sig);
      InvocationTargetException ite =
          assertThrows(
              InvocationTargetException.class,
              () -> checkArgumentMethod.invoke(null /* static method */, failingParams));

 *
 * <p><b>{@code default} method warning:</b> This class does <i>not</i> forward calls to {@code
 * default} methods. Instead, it inherits their default implementations. When those implementations
 * invoke methods, they invoke methods on the {@code ForwardingListenableFuture}.
 *
 * <p>Most subclasses can just use {@link SimpleForwardingListenableFuture}.
 *
 * @author Shardul Deo
 * @since 4.0
 */
@GwtCompatible

 *
 * <p><b>{@code default} method warning:</b> This class does <i>not</i> forward calls to {@code
 * default} methods. Instead, it inherits their default implementations. When those implementations
 * invoke methods, they invoke methods on the {@code ForwardingSortedMap}.
 *
 * <p>Each of the {@code standard} methods, where appropriate, use the comparator of the map to test
 * equality for both keys and values, unlike {@code ForwardingMap}.
 *

 *
 * <p><b>{@code default} method warning:</b> This class does <i>not</i> forward calls to {@code
 * default} methods. Instead, it inherits their default implementations. When those implementations
 * invoke methods, they invoke methods on the {@code ForwardingMultimap}.
 *
 * @author Robert Konigsberg
 * @since 2.0
 */
@GwtCompatible
public abstract class ForwardingMultimap<K extends @Nullable Object, V extends @Nullable Object>

 *
 * <p><b>{@code default} method warning:</b> This class does <i>not</i> forward calls to {@code
 * default} methods. Instead, it inherits their default implementations. When those implementations
 * invoke methods, they invoke methods on the {@code ForwardingSet}.
 *
 * <p>The {@code standard} methods are not guaranteed to be thread-safe, even when all of the
 * methods that they depend on are thread-safe.
 *
 * @author Kevin Bourrillion

 *
 * <p><b>{@code default} method warning:</b> This class does <i>not</i> forward calls to {@code
 * default} methods. Instead, it inherits their default implementations. When those implementations
 * invoke methods, they invoke methods on the {@code ForwardingMultimap}.
 *
 * @author Robert Konigsberg
 * @since 2.0
 */
@GwtCompatible
public abstract class ForwardingMultimap<K extends @Nullable Object, V extends @Nullable Object>

    T instance = invoke(factory, args);
    if (instance == null) {
      throw new FactoryMethodReturnsNullException(factory);
    }
    return instance;
  }

  private static <T> @Nullable T invoke(Invokable<?, ? extends T> factory, List<?> args)
      throws InvocationTargetException, IllegalAccessException {
    T returnValue = factory.invoke(null, args.toArray());
    if (returnValue == null) {