iOS.数据持久化.PersistenceLayer.Core Data

#import <Foundation/Foundation.h>
#import <CoreData/CoreData.h>

@interface Persistence04NoteCoreDataDAO : NSObject


//被管理的对象上下文
@property (readonly, strong, nonatomic) NSManagedObjectContext *managedObjectContext;
//被管理的对象模型
@property (readonly, strong, nonatomic) NSManagedObjectModel *managedObjectModel;
//持久化存储协调者
@property (readonly, strong, nonatomic) NSPersistentStoreCoordinator *persistentStoreCoordinator;

- (NSURL *)applicationDocumentsDirectory;

@end

#import "Persistence04NoteCoreDataDAO.h"

@implementation Persistence04NoteCoreDataDAO

@synthesize managedObjectContext = _managedObjectContext;
@synthesize managedObjectModel = _managedObjectModel;
@synthesize persistentStoreCoordinator = _persistentStoreCoordinator;


#pragma mark - Core Data 堆栈
//返回 被管理的对象上下文
- (NSManagedObjectContext *)managedObjectContext
{
    if (_managedObjectContext) {
        return _managedObjectContext;
    }
    
    NSPersistentStoreCoordinator *coordinator = [self persistentStoreCoordinator];
    if (coordinator) {
        _managedObjectContext = [[NSManagedObjectContext alloc] init];
        [_managedObjectContext setPersistentStoreCoordinator:coordinator];
    }
    return _managedObjectContext;
}

// 返回 持久化存储协调者
- (NSPersistentStoreCoordinator *)persistentStoreCoordinator
{
    if (_persistentStoreCoordinator) {
        return _persistentStoreCoordinator;
    }
    
    NSURL *storeURL = [[self applicationDocumentsDirectory] URLByAppendingPathComponent:@"CoreDataNotes.sqlite"];
    
    _persistentStoreCoordinator = [[NSPersistentStoreCoordinator alloc] initWithManagedObjectModel:[self managedObjectModel]];
    
    [_persistentStoreCoordinator addPersistentStoreWithType:NSSQLiteStoreType
                      configuration:nil
                                URL:storeURL
                            options:nil
                              error:nil];
    
    return _persistentStoreCoordinator;
}

//  返回 被管理的对象模型
- (NSManagedObjectModel *)managedObjectModel
{
    if (_managedObjectModel) {
        return _managedObjectModel;
    }
    NSURL *modelURL = [[NSBundle mainBundle] URLForResource:@"CoreDataNotes" withExtension:@"momd"];
    _managedObjectModel = [[NSManagedObjectModel alloc] initWithContentsOfURL:modelURL];
    return _managedObjectModel;
}

#pragma mark - 应用程序沙箱
// 返回应用程序Docment目录的NSURL类型
- (NSURL *)applicationDocumentsDirectory
{
    return [[[NSFileManager defaultManager] URLsForDirectory:NSDocumentDirectory inDomains:NSUserDomainMask] lastObject];
}

@end

#import <CoreData/CoreData.h>

#import "Persistence04NoteCoreDataDAO.h"
#import "Persistence04Note.h"
#import "NoteManagedObject.h"

@interface Persistence04NoteDAO : Persistence04NoteCoreDataDAO


+ (Persistence04NoteDAO*)sharedManager;

//插入Note方法
-(int) create:(Persistence04Note*)model;

//删除Note方法
-(int) remove:(Persistence04Note*)model;

//修改Note方法
-(int) modify:(Persistence04Note*)model;

//查询所有数据方法
-(NSMutableArray*) findAll;

//按照主键查询数据方法
-(Persistence04Note*) findById:(Persistence04Note*)model;

@end

#import "Persistence04NoteDAO.h"

@implementation Persistence04NoteDAO

static Persistence04NoteDAO *sharedManager = nil;

+ (Persistence04NoteDAO*)sharedManager
{
    static dispatch_once_t once;
    dispatch_once(&once, ^{
        
        sharedManager = [[self alloc] init];
        [sharedManager managedObjectContext];
        
    });
    return sharedManager;
}


//插入Note方法
-(int) create:(Persistence04Note*)model
{
    
    NSManagedObjectContext *cxt = [self managedObjectContext];
    
    NoteManagedObject *note = [NSEntityDescription insertNewObjectForEntityForName:@"Persistence04Note" inManagedObjectContext:cxt];
    [note setValue: model.content forKey:@"content"];
    [note setValue: model.date forKey:@"date"];
    
    note.date = model.date;
    note.content = model.content;
    
    NSError *savingError = nil;
    if ([self.managedObjectContext save:&savingError]){
        NSLog(@"插入数据成功");
    } else {
        NSLog(@"插入数据失败");
        return -1;
    }
    
    return 0;
}

//删除Note方法
-(int) remove:(Persistence04Note*)model
{
    
    NSManagedObjectContext *cxt = [self managedObjectContext];
    
    NSEntityDescription *entityDescription = [NSEntityDescription
                                              entityForName:@"Persistence04Note" inManagedObjectContext:cxt];
    
    NSFetchRequest *request = [[NSFetchRequest alloc] init];
    [request setEntity:entityDescription];
    
    NSPredicate *predicate = [NSPredicate predicateWithFormat:
                              @"date =  %@", model.date];
    [request setPredicate:predicate];
    
    NSError *error = nil;
    NSArray *listData = [cxt executeFetchRequest:request error:&error];
    if ([listData count] > 0) {
        NoteManagedObject *note = [listData lastObject];
        [self.managedObjectContext deleteObject:note];
        
        NSError *savingError = nil;
        if ([self.managedObjectContext save:&savingError]){
            NSLog(@"删除数据成功");
        } else {
            NSLog(@"删除数据失败");
            return -1;
        }
    }
    
    return 0;
}

//修改Note方法
-(int) modify:(Persistence04Note*)model
{
    NSManagedObjectContext *cxt = [self managedObjectContext];
    
    NSEntityDescription *entityDescription = [NSEntityDescription
                                              entityForName:@"Persistence04Note" inManagedObjectContext:cxt];
    
    NSFetchRequest *request = [[NSFetchRequest alloc] init];
    [request setEntity:entityDescription];
    
    NSPredicate *predicate = [NSPredicate predicateWithFormat:
                              @"date =  %@", model.date];
    [request setPredicate:predicate];
    
    NSError *error = nil;
    NSArray *listData = [cxt executeFetchRequest:request error:&error];
    if ([listData count] > 0) {
        NoteManagedObject *note = [listData lastObject];
        note.content = model.content;
        
        NSError *savingError = nil;
        if ([self.managedObjectContext save:&savingError]){
            NSLog(@"修改数据成功");
        } else {
            NSLog(@"修改数据失败");
            return -1;
        }
    }
    return 0;
}

//查询所有数据方法
-(NSMutableArray*) findAll
{
    NSManagedObjectContext *cxt = [self managedObjectContext];
    
    NSEntityDescription *entityDescription = [NSEntityDescription
                                              entityForName:@"Persistence04Note" inManagedObjectContext:cxt];
    
    NSFetchRequest *request = [[NSFetchRequest alloc] init];
    [request setEntity:entityDescription];
    
    NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"date" ascending:YES];
    [request setSortDescriptors:@[sortDescriptor]];
    
    NSError *error = nil;
    NSArray *listData = [cxt executeFetchRequest:request error:&error];
    
    NSMutableArray *resListData = [[NSMutableArray alloc] init];
    
    for (NoteManagedObject *mo in listData) {
        Persistence04Note *note = [[Persistence04Note alloc] init];
        note.date = mo.date;
        note.content = mo.content;
        [resListData addObject:note];
    }
    
    return resListData;
}

//按照主键查询数据方法
-(Persistence04Note*) findById:(Persistence04Note*)model
{
    NSManagedObjectContext *cxt = [self managedObjectContext];
    
    NSEntityDescription *entityDescription = [NSEntityDescription
                                              entityForName:@"Persistence04Note" inManagedObjectContext:cxt];
    
    NSFetchRequest *request = [[NSFetchRequest alloc] init];
    [request setEntity:entityDescription];
    
    NSPredicate *predicate = [NSPredicate predicateWithFormat:
                              @"date =  %@",model.date];
    [request setPredicate:predicate];
    
    NSError *error = nil;
    NSArray *listData = [cxt executeFetchRequest:request error:&error];
    
    if ([listData count] > 0) {
        NoteManagedObject *mo = [listData lastObject];
        
        Persistence04Note *note = [[Persistence04Note alloc] init];
        note.date = mo.date;
        note.content = mo.content;
        
        return note;
    }
    return nil;
}



@end