Hi, i don't know what's wrong. I started testing with code below.
public static void main(String[] args) {
        IncomeDataAdapter IDA = new IncomeDataAdapter();
        IDA.getPhoneNumber();
    }
I made a default contructor in IncomeDataAdapter class
        public IncomeDataAdapter() {

        }
public String getPhoneNumber() {
    String txt= "123456";//Integer.toString(data.getPhoneNumber());
    String countryCode = "1";//data.getCountryCode();
    String answer = "";

    while(number.length() < 10){
        number = "0" + number;
    }


    answer = answer + "+" + countryCode + "(" +
            txt.substring(0,3) + ")" +
            txt.substring(3,6) + "-" +
            txt.substring(6,8) + "-" +
            txt.substring(8,10);
    System.out.println(answer);
    return answer;
}
answers: 123456 -> +1(000)012-34-56 0 -> +1(000)000-00-00 1 -> +1(000)000-00-01