How to retrieve all entities in one collection using android sdk

can any one tell that how to retrieve all entities in particular collection.. Though i am using getEntitiesAsync() by passing String type="my collection name", String query="null"/ null , and response callback but it gives null response.

And My according to my second requirement if i want entities by particular user i am querying my data like this: String type="collection name", String query="user='uuid'"; but still showing me an error in parsing query.