How to concat two ArrayLists?

Question

I have two ArrayLists of equal size. List 1 consists of 10 names and list 2 consists of their phone numbers.

I want to concat the names and number into

Answer 1

add one ArrayList to second ArrayList as:

Arraylist1.addAll(Arraylist2);

EDIT : if you want to Create new ArrayList from two existing ArrayList then do as:

ArrayList arraylist3=new ArrayList();

arraylist3.addAll(Arraylist1); // add first arraylist

arraylist3.addAll(Arraylist2); // add Second arraylist