@Override
    public boolean equals(Object obj) {
        if (this == obj) return true;
        if (obj == null) return false;
        if (getClass() != obj.getClass()) return false;
        Account other = (Account) obj;
        if (id == null) {
            if (other.id != null) return false;
        } else if (!id.equals(other.id)) return false;
        return true;
    }