class Ideone {
    public static void main (String[] args)  {
        String bigger = "I AM IN AMSTERDAM", smaller = "AM";
        System.out.println( asPartOfString(bigger, smaller));
        System.out.println( asPartOfWord(bigger, smaller));
    }
    static int asPartOfString(String main,String search){
        return main.split(search, -1).length - 1;
    }
    static int asPartOfWord(String main,String search){
        return main.split("\\b" + search + "\\b", -1).length - 1;
    }
}

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