Grails one-to-many in one direction

[J Solomon]

New to grails here and I'm looking to model a one-to-many relationship, but I only want creates and updates to work in one direction.

class Env {
    String environmentName

    static hasMany = [functionalAreas : FunctionalArea, propertiesFiles : PropertiesFile]

    static constraints = {
        environmentName(nullable : false)
        functionalAreas()
        propertiesFiles()
    }
}

class PropertiesFile {
    String propertiesFileName
    String directory

    static belongsTo = [env : Env]

    static constraints = {
        propertiesFileName(nullable : false)
        directory(nullable : false)
        env()
    }
}

So what I'm looking for is when I create a new environment, I don't want to be able to add PropertiesFiles to it, since you cannot have a properties file without first having an Environment (kinda like the whole chicken and egg thing). When I create a new Properties file, you should have to associate it with a pre-existing Environment. I hope this makes sense. Thanks for the help in advance.

[Gregg Bolinger]

This is not something that you control with your Domain relationships. This is something you control with business logic in your Controller/Service as well your views.