剔除孤儿数据
删除孤儿数据
//获得set，清空
umpActivity.getUmpActivityTypeSet().clear();
//设置新值，会将新的数据加进去，原来的全部会被删掉，因为 @Cascade(org.hibernate.annotations.CascadeType.ALL)
umpActivity.getUmpActivityTypeSet().addAll(newUmpActivityTypeSet);
@OneToMany(cascade = { CascadeType.ALL }, mappedBy = "umpActivity", fetch = FetchType.EAGER)
@Cascade(org.hibernate.annotations.CascadeType.ALL)
@JoinColumn(name = "activity_id")
@OrderBy("umpType")
public Set<UmpActivityType> getUmpActivityTypeSet() {
return umpActivityTypeSet;
}