package com.tcm.training.admin.common;

public class PhoneMasker {

    private PhoneMasker() {
    }

    public static String mask(String phone) {
        if (phone == null) {
            return null;
        }
        String p = phone.trim();
        if (p.length() < 7) {
            return p;
        }
        return p.substring(0, 3) + "****" + p.substring(p.length() - 4);
    }
}