Override getter and setter in grails domain class for relation

问题

How to override getter and setter for field being a relation one-to-many in grails domain class? I know how to override getters and setters for fields being an single Object, but I have problem with Collections. Here is my case:

I have Entity domain class, which has many titles. Now I would like to override getter for titles to get only titles with flag isActive equals true. I've tried something like that but it's not working:

class Entity {

    static hasMany = [
        titles: Title
    ]

    public Set<Title> getTitles() {
        if(titles == null)
            return null
        return titles.findAll { r -> r.isActive == true }
    }

    public void setTitles(Set<Title> s) {
        titles = s
    }
}

class Title {
    Boolean isActive

    static belongsTo = [entity:Entity]

    static mapping = {
        isActive column: 'is_active'
        isActive type: 'yes_no'
    }
}

Thank You for your help.

回答1:

Need the reference Set<Title> titles.

class Entity {
    Set<Title> titles

    static hasMany = [
        titles: Title
    ]

    public Set<Title> getTitles() {
        if(titles == null)
            return null;
        return titles.findAll { r -> r.isActive == true }
    }

    public void setTitles(Set<Title> s) {
        titles = s
    }
}

来源：https://stackoverflow.com/questions/17169657/override-getter-and-setter-in-grails-domain-class-for-relation