This project contains classes to help you persist objects and collections of objects as well as sync multiple copies of those objects and collections so they're all up to date.
##Persistent Objects
NAPersistentObject: a class that helps you persist data
NAPersistentObject makes it easy to persist an object of any subclass to disk (or a collection of those objects)
by automatically coding all properties defined in the subclass as long as they are NSCoding compliant (including
other objects that derive from NAPersistentObject).
Example:
@interface MyObj : public NAPersistentObject
@property (nonatomic, copy) NSString *myData;
@end
@implementation MyObj
@end
...
MyObj *obj1 = [[MyObj alloc] init];
obj1.myData = @"some data";
NSString *path = [NSTemporaryDirectory() stringByAppendingPathComponent:@"persistentTest.dat"];
[obj1 writeToFile:path];
MyObj *obj2 = [MyObj loadFromFile:path];
##Syncable Objects
NASyncableObject is a subclass of NAPersistentObject. A subclass of NASyncableObject is able to synchronize changes to any of its properties with another object of the same class by automatically tracking modification times. Syncing can go in one direction or both directions.
Example:
@interface MyObj : public NASyncableObject
@property (nonatomic, copy) NSString *d1;
@property (nonatomic, copy) NSString *d2;
@property (nonatomic, copy) NSString *d3;
@end
@implementation MyObj
@end
...
MyObj *obj = [[MyObj alloc] init];
obj1.d1 = @"1";
obj1.d2 = @"2";
obj1.d3 = @"3";
NSString *path = [NSTemporaryDirectory() stringByAppendingPathComponent:@"persistentTest.dat"];
[obj1 writeToFile:path];
MyObj *obj2 = [MyObj loadFromFile:path];
obj2.d1 = @"5"; // obj2 now has d1=@"5", d2=@"2", d3=@"3"
obj1.d3 = @"6"; // obj1 now has d1=@"1", d2=@"2", d3=@"6"
[obj1 syncWith:obj2]; now both have d1=@"5", d2=@"2", d3=@"6"
##Syncable Collections
An NASyncableCollection object is a persistable container of NASyncableObject entities. The collection tracks additions, deletions and the latest modification date of any member entity and can sync with another NASyncableCollection object so both end up with the same entities and each of those entities have been synced with each other.
Each entity is referenced in the collection by its unique identifier (its uid property). And of course, since the collection is an NAPersistentObject as well, the whole collection can be persisted to storage.