英文:
Sort by count in spring mvc, for a OneToMany variable
问题
以下是翻译好的内容：
我在我的 Spring 应用程序中有两个类：
@Entity
@Table(name = "events")
public class Event {
@Id
@GeneratedValue
private long id;
@ManyToOne
@JoinColumn(name = "venue_fk")
private Venue venue;
// 设置器，获取器...
}
以及
@Entity
@Table(name = "venues")
public class Venue {
@Id
@GeneratedValue
private long id;
private String name;
@OneToMany
private Set<Event> events = new HashSet<>();
// 设置器，获取器...
}
我想要做的事情是在 VenueService 中编写一个方法，返回 Iterable<Venue>，并且根据它们拥有的事件数量（降序）和场馆名称（升序）在这个可迭代对象中呈现场馆对象，拥有更多事件的场馆会优先出现。
例如，我有三个场馆，venueA 注册了 3 个事件，venueB 注册了 3 个事件，而 venueC 注册了 4 个事件，那么方法 findAllVenuesByNoOfEvents() 应该返回按顺序排列的 Iterable<Venue>，顺序为 venueC、venueA、venueB。
我对 Spring 还很陌生，真的不知道如何做这个，提前感谢您的帮助。
英文:
I have two classes in my spring application:
@Entity
@Table(name = "events")
public class Event {
@Id
@GeneratedValue
private long id;
@ManyToOne
@JoinColumn(name = "venue_fk")
private Venue venue;
// Setters, getters...
}
and
@Entity
@Table(name = "venues")
public class Venue {
@Id
@GeneratedValue
private long id;
private String name;
@OneToMany
private Set<Event> events = new HashSet<>();
// Setters, getters...
}
The thing I want to do is to write a method in VenueService that returns Iterable<Venue> and venue objects appear in this Iterable based on how many events they have (DESC) and then venue name(ASC), the more events one venue has, the earlier it appears.
E.g. I have three venues, venueA has 3 events registered with it, venueB has 3 events registered with it, and venueC has 4 events registered with it, then the method findAllVenuesByNoOfEvents() should return Iterable<Venue> in the order venueC, venueA, venueB.
I'm new to spring and I'm really don't know how to do this, thanks in advance.
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