class InMemoryKey {

  public InMemoryKey(InMemoryKey parentKey, String kind, String name) {
    if (null == kind) {
      throw new IllegalArgumentException("Kind cannot be null");
    }
    this.parentKey = parentKey;
    this.kind = kind;
    this.name = name;
  }

  public  InMemoryKey(InMemoryKey parentKey, String kind, String name);

}