如何查找域对象关联类参数？

Question

我有域类workpackage，activity和aw。
如何从workpackage获取活动id值。

class Aw {

    Activity activity    
    static hasMany=[activity:Activity]    
    Workpackage workpackage 

    static belongsTo=[workpackage:Workpackage]

    static constraints = {

        workpackage nullable:true    
        activity nullable:true
    }
}

Answer 1

Workpackage有很多活动。就是这样。没有PW或AW类。如果您想从活动中获取项目ID，只需写入 def myactivity = Activity.get(passed_id); def wanted_id = my_activity.workpackage.project.id.

如果我没有正确理解这个问题，请详细解释。