我有以下自引用域类:
package com.test
import org.bson.types.ObjectId
class Category {
ObjectId id
String name
Category parent = null
static hasMany = [childs: Category]
static mappedBy = [ childs: 'childs' ]
}
然后,我创建2个“类别”对象,其中第二个对象成为第一个对象的子对象,如下所示:
def c1 = Category.findByName('category1') ?: new Category(name: 'category1').save(failOnError: true)
def c2 = Category.findByName('category2') ?: new Category(name: 'category2', parent: c1).save(failOnError: true)
c1.addToChilds(c2).save(failOnError: true)
结果不是我所期望的,并且似乎两个对象成为另一个对象的子对象:
{
"_id" : ObjectId("5b8d0ba306425e3ee4ff5cf9"),
"name" : "category1",
"version" : NumberLong(0),
"childs" : [
ObjectId("5b8d0ba306425e3ee4ff5cfa")
]
}
{
"_id" : ObjectId("5b8d0ba306425e3ee4ff5cfa"),
"name" : "category2",
"version" : NumberLong(0),
"childs" : [
ObjectId("5b8d0ba306425e3ee4ff5cf9")
],
"parent" : ObjectId("5b8d0ba306425e3ee4ff5cf9")
}
虽然我可以简单地忽略那些也是父母的孩子,但为什么我会有这种奇怪的举动?