摘要：
@ManyToMany(mappedBy = "friends", cascade = { CascadeType.PERSIST }, fetch = FetchType.LAZY) private List<User> owns; @ManyToMany(cascade = { CascadeType.PERSIST }, fetch = FetchType.LAZY) @JoinTable(name = "friends_middle", joinColumns = { @JoinColumn(name = "friendsI 阅读全文