char arraylist java

1  import java.util.ArrayList;
2
3  public class Test{
4
5       String words = new String("HELLO GOODBYE!");
6       ArrayList<Character> sample = new ArrayList<Character>();
7
8       for(int i = 0; i<words.length(); i++){
9           sample.add(words.charAt(i));
10       }
11  }

1ArrayList<Character> operations = new ArrayList<Character>();