methods in Java Enum

OrderState.java

// @see https://github.com/madvirus/ddd-start

public enum OrderState {
  PAYMENT_WAITING {
    public boolean isShippingChangeable() {
      return true;
    }
  }, PREPARING {
    public boolean isShippingChangeable() {
      return true;
    }
  },
  SHIPPED, DELIVERING, DELIVERY_COMPLETED, CANCELED;

  public boolean isShippingChangeable() {
    return true;
  }
}