不会在核心数据swift中保存int

Question

我想将Int保存到我的核心数据中，现在我这样做但它在Int上崩溃并且只保存了1个项目。

let appDel: AppDelegate = UIApplication.sharedApplication().delegate as AppDelegate

let context: NSManagedObjectContext = appDel.managedObjectContext!
let ent = NSEntityDescription.entityForName("Groups", inManagedObjectContext: context)

var newItem = Groups(entity: ent!, insertIntoManagedObjectContext: context)

我的代码

if let groups : AnyObject! = json {
    //println(groups["groups"])

    var group = groups["groups"] as NSArray

    for g in group{

        newItem.id = g["id"] as Int
        newItem.name = g["name"] as NSString

        context.save(nil)
        println(newItem)

        println(g["id"] as Int)
        //println(g["name"] as NSString)
    }
}

型号：

@objc(Groups)
class Groups: NSManagedObject {

    @NSManaged var id:Int
    @NSManaged var name:String
}

Consolelog：

nil
<NSManagedObject: 0x7fe0c9f2f520> (entity: Groups; id: 0xd000000000140000 <x-coredata://1405B706-2AC6-4CED-BED5-FE0232723976/Groups/p5> ; data: {
    "group_id" = nil;
    id = 0;
    name = Press;
})
1
<NSManagedObject: 0x7fe0c9f2f520> (entity: Groups; id: 0xd000000000140000 <x-coredata://1405B706-2AC6-4CED-BED5-FE0232723976/Groups/p5> ; data: {
    "group_id" = nil;
    id = 0;
    name = Sales;
})
2
<NSManagedObject: 0x7fe0c9f2f520> (entity: Groups; id: 0xd000000000140000 <x-coredata://1405B706-2AC6-4CED-BED5-FE0232723976/Groups/p5> ; data: {
    "group_id" = nil;
    id = 0;
    name = "Other information";
})
3