java - tree like data structure in java

Question

I want to implement a tree like data structure in java for activity objects, where nodes can be shared between two parents. I want to build a hierarchy of activities, where one activity can be contained by multiple activities. How can I do it? Or should I use some other data structure and how?

Answer 1

像这样的东西应该工作：

public class Activity {

    private Activity parent1;
    private Activity parent2;
    private List<Activity> children;

    // other fields, getters, setters, methods, etc    

}

Answer 2

要决定设计，了解如何导航结构至关重要。如果只是自上而下，您所需要的只是让 Activity 包含其子项的列表。如何确保最多两个活动拥有某个活动是另一回事。如果您需要确保这一点，那么您可能需要在活动中使用父参考。