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class CloneExample implements Cloneable {
  HttpCookie[] cookies;

  CloneExample(HttpCookie[] c) {
    cookies = c;
  }

  public Object clone() throws CloneNotSupportedException {
    final CloneExample clone = (CloneExample) super.clone();
    clone.doSomething(); // Invokes overridable method
    clone.cookies = clone.deepCopy();
    return clone;
  }

  void doSomething() { // Overridable
    for (int i = 0; i < cookies.length; i++) {
      cookies[i].setValue("" + i);
    }
  }

  HttpCookie[] deepCopy() {
    if (cookies == null) {
      throw new NullPointerException();
    }

    // deep copy
    HttpCookie[] cookiesCopy = new HttpCookie[cookies.length];

    for (int i = 0; i < cookies.length; i++) {
      // Manually create a copy of each element in array
      cookiesCopy[i] = (HttpCookie) cookies[i].clone();
    }
    return cookiesCopy;
  }
}

class Sub extends CloneExample {
  Sub(HttpCookie[] c) {
    super(c);
  }

  public Object clone() throws CloneNotSupportedException {
    final Sub clone = (Sub) super.clone();
    clone.doSomething();
    return clone;
  }

  void doSomething() { // Erroneously executed
    for (int i = 0;i < cookies.length; i++) {
      cookies[i].setDomain(i + ".foo.com");
    }
  }

  public static void main(String[] args)
      throws CloneNotSupportedException {
    HttpCookie[] hc = new HttpCookie[20];
    for (int i = 0 ; i < hc.length; i++){
      hc[i] = new HttpCookie("cookie" + i,"" + i);
    }
    CloneExample bc = new Sub(hc);
    bc.clone();
  }
}