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102 lines
4.5 KiB
Objective-C
102 lines
4.5 KiB
Objective-C
//
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// NSManagedObjectContext+RKAdditions.h
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// RestKit
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//
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// Created by Blake Watters on 3/14/12.
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// Copyright (c) 2009-2012 RestKit. All rights reserved.
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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//
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#import <CoreData/CoreData.h>
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@class RKManagedObjectStore;
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/**
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Provides extensions to `NSManagedObjectContext` for various common tasks.
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*/
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@interface NSManagedObjectContext (RKAdditions)
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///---------------------------------
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/// @name Inserting a Managed Object
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///---------------------------------
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/**
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Inserts a new managed object for the entity for the given name.
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This method is functionally equivalent to the follow code example.
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[NSEntityDescription insertNewObjectForEntityForName:entityName inManagedObjectContext:self];
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@param entityName The name of an entity.
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@return A new, autoreleased, fully configured instance of the class for the entity named entityName. The instance has its entity description set and is inserted into the receiver.
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*/
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- (id)insertNewObjectForEntityForName:(NSString *)entityName;
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///-------------------------------
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/// @name Counting Managed Objects
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///-------------------------------
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/**
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Convenience method for performing a count of the number of instances of an entity with the given name.
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This method is functionally equivalent to the following code example.
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NSError *error;
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NSFetchRequest *fetchRequest = [NSFetchRequest fetchRequestWithEntityName:entityName];
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fetchRequest.predicate = predicate;
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NSUInteger count = [managedObjectContext countForFetchRequest:fetchRequest error:&error];
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@param entityName The name of an entity.
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@param predicate A predicate to limit the search. May be nil.
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@param error If there is a problem executing the fetch, upon return contains an instance of NSError that describes the problem.
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@return The number of objects a fetch request for the given entity name with the given predicate would have returned if it had been passed to executeFetchRequest:error:, or NSNotFound if an error occurs.
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*/
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- (NSUInteger)countForEntityForName:(NSString *)entityName predicate:(NSPredicate *)predicate error:(NSError **)error;
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///----------------------------------------------
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/// @name Fetching Managed Objects by Primary Key
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///----------------------------------------------
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/**
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Fetches a single managed object for the given entity with the given value for the primary key attribute in the receiver.
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@param entity The entity of the managed object to be retrieved by primary key.
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@param primaryKeyValue The value for the entity's primary key attribute.
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@return The managed object with the primary key attribute equal to the given value or nil if none was found.
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*/
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- (id)fetchObjectForEntity:(NSEntityDescription *)entity withValueForPrimaryKeyAttribute:(id)primaryKeyValue;
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/**
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Fetches a single managed object for the entity for the given name with the given value for the primary key attribute in the receiver.
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@param entityName The name of the entity of the managed object to be retrieved by primary key.
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@param primaryKeyValue The value for the receiving entity's primary key attribute.
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@return The managed object with the primary key attribute equal to the given value or nil if none was found.
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*/
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- (id)fetchObjectForEntityForName:(NSString *)entityName withValueForPrimaryKeyAttribute:(id)primaryKeyValue;
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///-------------------------------------------------
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/// @name Saving the Context to the Persistent Store
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///-------------------------------------------------
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/**
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Saves the receiver and then traverses up the parent context chain until a parent managed object context with a nil parent is found. If the final ancestor context does not have a reference to the persistent store coordinator, then a warning is generated and the method returns NO.
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@param error If there is a problem saving the receiver or any of its ancestor contexts, upon return contains an pointer to an instance of NSError that describes the problem.
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@return YES if the save to the persistent store was successful, else NO.
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*/
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- (BOOL)saveToPersistentStore:(NSError **)error;
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@end
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