private static Component hash(Component component) {
    EKey[] ids = component.ids;
    EKey[] hashedKeys = new EKey[ids.length];
    for (int i = 0; i < ids.length; i++) {
      hashedKeys[i] = ids[i].hashed();
    }
    return new Component(component.value, hashedKeys);
  }
private static Component hash(Component component)