Core Data中的对象关系图

nameNSString

mom = managedObjectModelmoc = managedObjectContextmo = managedObjectps = persistentStorepsc = persistentStoreCoordinatorQ1: How to get mom from moc:moc---momA1: mom = moc.psc.momQ2: mom--entityA2: [mom.entities objectForKey:entityName]因此在NSEntityDescription中就有一个集合了A1 A2功能的函数：moc-entityentityForName: inManagedObjectContext:Q3:How to create a new mo in certain moc with specified entity:[[NSManagedObject alloc] initWithEntity:insertInToManagedObjectContext:] 同样的，NSEntityDescription中从entityName 到 mo的便利函数是：insertNewObjectForEntityForName:inManagedObjectContext:

cacheNodeSetNSSet

objectIDNSManangedObjectID

objectIDNSManagedObjectID

等价

managedObjectNSManagedObject

managedObjectContextNSManagedObjectContext

value

NSAtomicStoreCacheNode

attributeNSAttributeDescription

URIRepresentationNSURL

父类：NSPersistentStore

存储

辅助存储系统

relationship关系

configurationsNSArray

[managedObject valueForKey: key]

configurationNameNSString

父类：NSPropertyDescription

fetchRequestTemplateForName：NSFetchRequest

entity.properties

cacheNodesNSAtomicStoreCacheNode

properties=[attributesByName allKeys] + [relationshipsByName allKeys]NSArray

allValues

entitiesByNameNSDictionary (value:NSEntityDescription)

atomicStoreNSAtomicStore

persistentStoresNSArray

NSManagedObject

cacheNodeNSAtomicStoreCacheNode

NSAtomicStore

propertyCacheNSMutableDictionary

Two layers inside Core Data

User Code

destinationEntityNSEntityDescription

urlNSURL

propertiesByNameNSDictionary

attributesByNameNSDictionary

relationshipsByNameNSDictionary

entitiesNSArray (NSEntityDescription)

metadataNSDictionary

attributeNameNSString

registeredStoreTypesNSDictionary

persistentStoreCoordinatorNSPersistentStoreCoordinator

managedObjectModelNSManangedObjectModel

NSAtomicStore层对象关系图

key

NSManagedObjectContext

relationshipNameNSString

inverseRelationshipNSRelationshipDescription

objectAtIndex:

attribute属性

persistentStoreNSPersistentStore

managedObjectClassNameNSString

entityNSEntityDescrption

attributeTypeNSAttribute

undoManangerNSUndoManager

relationshipNSRelationshipDescription