泛化调用中
```java
public interface GenericService {

    Object $invoke(String method, String[] parameterTypes, Object[] args) throws GenericException;

}
```
这里可不可以异步调用返回个Future。我的工具实现会有多个 `ReferenceConfig` 缓存，我可以单独再用一个线程池来作为 `$invoke` 的执行上下文。但每个 `ReferenceConfig` 好像都有一组线程来维持，这个本身能不能异步调用？
final Object onInvokeInst = asyncMethodInfo.getOninvokeInstance();
        if (onInvokeMethod == null && onInvokeInst == null) {
            return;
        }
        if (onInvokeMethod == null || onInvokeInst == null) {
            throw new IllegalStateException("service:" + invoker.getUrl().getServiceKey() + " has a oninvoke callback config , but no such " + (onInvokeMethod == null ? "method" : "instance") + " found. url:" + invoker.getUrl());
        }
        if (!onInvokeMethod.isAccessible()) {
            onInvokeMethod.setAccessible(true);
        }
        Object[] params = invocation.getArguments();
        try {
            onInvokeMethod.invoke(onInvokeInst, params);
        } catch (InvocationTargetException e) {
            fireThrowCallback(invoker, invocation, e.getTargetException());
        } catch (Throwable e) {
            fireThrowCallback(invoker, invocation, e);
        }
    }
    private void fireReturnCallback(final Invoker<?> invoker, final Invocation invocation, final Object result) {
        final ConsumerMethodModel.AsyncMethodInfo asyncMethodInfo = getAsyncMethodInfo(invoker, invocation);
        if (asyncMethodInfo == null) {
            return;
        }
        final Method onReturnMethod = asyncMethodInfo.getOnreturnMethod();
        final Object onReturnInst = asyncMethodInfo.getOnreturnInstance();
        
        if (onReturnMethod == null && onReturnInst == null) {
            return;
        }