Question

I have an Arraylist. If user enter the same number secondly I want to show to user. For this I need to find Arraylist have it or not.

I hope I made myself clear.

Answer 1

If you are checking to see if some value is stored in an ArrayList you can use the contains() method, this will return true if the object is in the list, false otherwise.

ArrayList<Integer> intList = new ArrayList<>();

intList.add(5);
intList.add(7);
intList.add(3);
intList.add(-2);

intList.contains(-1); //returns false
intList.contains(3); //returns true