Question

只是想知道是否有人可以建议域类架构应该如何。我有一个名为Category的域类，但可能存在具有相同域（类别）的子类。例如，设备Toaster可以属于Kitchen，子类别SmallAppliance。

class Category {
   static hasMany = [appliances: Appliance, categories: Category] 
   String name
}

class Appliance {
   static belongsTo = Category
   static hasMany = [categories: Category]
}

Answer 1

Appliance域类需要进行一些小调整。猜一下！！：）

我们Appliance categories中不需要hasMany关系。这种关系是这样的：

Category --> SubCategory (type of Category) --> Appliance

设备belongsTo父类别以及subCategory，而Category本身就是class Appliance { static belongsTo = Category String name } class Category { String name static hasMany = [appliances: Appliance, subCategories: Category] }。因此，在设备中，belongsTo关系就足够了。

使用相反：

//Category
def kitchen = new Category(name: "Kitchen")
kitchen.save()

//Appliance
def toaster = new Appliance(name: "Toaster")
kitchen.addToAppliances(toaster)
kitchen.save()

//Sub Categories
def electrical = new Category(name:  "Electrical")
//Electrical category is a sub category of Kitchen
kitchen.addToSubCategories(electrical)

//Toaster is an appliance of Category Kitchen and Sub Category Electrical
electrical.addToAppliances(toaster)
kitchen.save()

assert kitchen
assert toaster
assert electrical

assert kitchen.appliances.size() == 1
kitchen.appliances.each{assert it.name == 'Toaster'}

assert kitchen.subCategories.size() == 1
kitchen.subCategories.each {assert it.name == 'Electrical'}

assert electrical.appliances.size() == 1
electrical.appliances.each {assert it.name == 'Toaster'}

这是一个可以更好地理解事物的测试用例：

{{1}}

让我们知道它是否仍然不清楚。

GORM：有很多相同的域类

1 个答案: