How do I declare a 2D String arraylist?

arraylist, arrays, java

Solution

You can go with

List<List<String>> ls2d = new ArrayList<List<String>>();
List<String> x = new ArrayList<String>();
x.add("Hello");
x.add("world!");
ls2d.add(x);

System.out.println(Arrays.deepToString(ls2d.toArray()));

Problem

I want to do something like this `ArrayList<String<String>> mylist` How can I create it? How can I add to the external and internal list and how can I convert the internal list to a simple array list?

Original source

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