Basically you've got the hierarchy like this:
AmazonDynamoDBAsync
^
|
-----------------------------
| |
AmazonDynamoDBAsyncClient AsyncClient
And you are trying to cast AmazonDynamoDBAsyncClient
instance to AsyncClient
, which isn't possible. Those are siblings. Take it like this: "Apple" and "Banana" are both "Fruit", but an "Apple" is not a "Banana".