What is the ideal Grails class domain for this tree structure

Question

I'm developing a website that need categories with sub categories.

My current domain class is:

package com.abc

class Category {

    String title
    String description
    Category parent

    static hasMany = [children: Category, listing: Listing]

    static constraints = {
        title blank: false
        description blank: true
    } 
}

But it gives me an error:

Property [children] in class [class com.abc.Category] is a bidirectional one-to-many with two possible properties on the inverse side. Either name one of the properties on other side of the relationship [category] or use the 'mappedBy' static to define the property that the relationship is mapped with. Example: static mappedBy = [children:'myprop']

So what is the question? see how to use mappedby http://grails.org/doc/2.2.x/ref/Domain%20Classes/mappedBy.html and configure properly. Also you need relation either to parent or to children as usual — Mr. Cat, May 21 '13 at 07:45

score 4 · Answer 1 · answered May 21 '13 at 07:15

4

I would use only Category parent. We can always get children by Category.findAllByParent. This is also the easiest solution to use later on in tree creation.

answered May 21 '13 at 07:15

Grzegorz Gajos

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What is the ideal Grails class domain for this tree structure

1 Answers1