How to insert an object in an ArrayList at a specific position

Question

Suppose I have an ArrayList of objects of size n. Now I want to insert an another object at specific position, let\'s say at index position k (is greater than 0 and less tha

Answer 1

For example:

I want to move the element from 23th to 1th(index == 0) in the arrayList, so I put 23th element to a temp value, and removing from list, insert it to 1th in list. It's worked, but not more efficient.

 List list = JSON.parseArray(channelJsonStr,ItemBean.class);
    for (int index = 0; index < list.size(); index++) {
        if (list.get(index).getId() == 23) { // id 23
            ItemBean bean = list.get(index);
            list.remove(index);
            list.add(0, bean);
        }
    }