how to split a string every characters java code example

Example 1: split every character in string into array java

String s="abcd";
char[] a=s.toCharArray();

Example 2: split string 2 characters java

String str= "abcdef";

        String[] array=str.split("(?<=\\G.{2})");

        System.out.println(java.util.Arrays.toString(array));