一个字符串包含另一个字符串的个数

    public static int countStr(String str1, String str2) {
        int count = 0;
        while (str1.contains(str2) && str1.length() > str2.length()) {
            str1 = str1.substring(str1.indexOf(str2) + 1);
            count++;
        }
        return count;
    }

    public static void main(String[] args) throws Exception {
        int i = countStr("222", "2");
        System.err.println(i);//3
    }