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package factory.person;
import java.util.Random;
public class PersonFactory {
  private PersonFactory() {}
  static private Random random = new Random();
  static public SSN newSSN(String s) {
    final int REQUIREDLENGTH = 9;
    if (null == s || REQUIREDLENGTH != s.length())
      throw new IllegalArgumentException();
    boolean someNonZeroDigit = false;
    for (int i=0; i<REQUIREDLENGTH; i++) {
      char c = s.charAt(i);
      if (!Character.isDigit(c))
        throw new IllegalArgumentException();
      if (0 != Character.digit(c,10))
        someNonZeroDigit = true;
    }
    if (!someNonZeroDigit)
      throw new IllegalArgumentException();
    return new SSNObj(s);
  }
  static public Person newRandomPerson() {
    return new PersonObj(Integer.toString(random.nextInt()),SSN.INVALID);
  }
  static public Person newPerson(String name, String ssn) {
    return new PersonObj(name,ssn);
  }
  static public Person newPerson(String name, SSN ssn) {
    return new PersonObj(name,ssn);
  }
}

final class SSNObj implements SSN {
  final private String s;
  final private long l;
  SSNObj(String s) {
    this.s = s;
    this.l = Long.parseLong(s);
  }
  public String toString() { return s; }
  public long toLong() { return l; }
  // TODO: define equals, hashcode, compareTo
  public int compareTo(SSN that) { return -1; }
}

final class PersonObj implements Person {
  final private String name;
  final private SSN ssn;
  PersonObj(String name, SSN ssn) {
    if (null == name || 0 == name.trim().length())
      throw new IllegalArgumentException();
    this.name = name.trim();
    this.ssn = ssn;
  }
  PersonObj(String name, String ssn) {
    this(name,PersonFactory.newSSN(ssn));
  }
  public String name() { return name; }
  public SSN ssn() { return ssn; }
  // TODO: define equals, hashcode, compareTo
  public int compareTo(Person that) { return -1; }
}