class Aer implements Comparable<Aer> {

  @Override
  public int compareTo(final Aer other) {
    assertNotNull(other, "Other is null");
    return this.value.compareTo(other.value);
  }

  public  Aer(final String amount);
  public  Aer(final String amount, final Unit unit);
  public  Aer(final BigInteger amount);
  protected  Aer();

}