Question

In C# there is DataTable type which can be used to create multi-column structures. In java I can use nested hashmaps but its too complicated structure even if you have 3 columns. Does core java support any such structure without including any external library?

I can use multidimensional arrays but still checking for any possible option.

Answer 1

Java has no directly available table format. However, we can use the generics functionality to our advantage here. You can read about them here. Instantiation will look like this

Map<String, List<String>> tableMap = new HashMap<String, List<String>>();

Now, you have a 2D structure with an identifier String for every row, and the rest of the row stored as a list. You do need to choose unique identifiers for each row though, so if you are aiming to map it with a table (as you do in C#), make sure that the key of the HashMap is the primary key of the table.

I hope that helped.