Answer 1

Instead of using a 2D array, you should use something more like a dictionary which uses key value pairs to store a variety of information.

Info = {Name: "Short sword", Price: 100};

Answer 2

You can test your data to tell which class it is (using instanceof.) Then, type cast it.
https://www.webucator.com/how-to/how-check-object-type-java.cfm