how to change an arraylist to a array in java code example

Example 1: java arraylist to array

List<String> list = new ArrayList<>();
list.add("a");
list.add("ab");
list.add("abc");
list.add("abcd");
// convert
String[] array = list.toArray();

Example 2: convert arraylist to array in java

Integer[] arr = new Integer[al.size()]; 
for (int i = 0; i < al.size(); i++) 
     arr[i] = al.get(i);