YapDatabase 学习笔记三

YapDatabase可以直接储存（序列化）对象，包括自定义对象，但是你要让对象实现NSCoding协议。
当然，也可以自己向YapDatabase提供序列化／反序列化对象。自己去实现这一过程。

- (id)initWithPath:(NSString *)path
    serializer:(YapDatabaseSerializer)serializer
  deserializer:(YapDatabaseDeserializer)deserializer;

(id)initWithPath:(NSString *)path objectSerializer:(YapDatabaseSerializer)objectSerializer

objectDeserializer:(YapDatabaseDeserializer)objectDeserializer

metadataSerializer:(YapDatabaseSerializer)metadataSerializer

metadataDeserializer:(YapDatabaseDeserializer)metadataDeserializer;

/**

• The default serializer & deserializer use NSCoding (NSKeyedArchiver & NSKeyedUnarchiver).

• Thus any objects that support the NSCoding protocol may be used.
  *

• Many of Apple's primary data types support NSCoding out of the box.

• It's easy to add NSCoding support to your own custom objects.
  **/

• (YapDatabaseSerializer)defaultSerializer;

• (YapDatabaseDeserializer)defaultDeserializer;

/**

• Property lists ONLY support the following: NSData,NSString,NSArray,NSDictionary,NSDate,and NSNumber.

• Property lists are highly optimized and are used extensively by Apple.

• Property lists make a good fit when your existing code already uses them,

• such as replacing NSUserDefaults with a database.
  **/

• (YapDatabaseSerializer)propertyListSerializer;

• (YapDatabaseDeserializer)propertyListDeserializer;

/**

• A FASTER serializer & deserializer than the default,if serializing ONLY a NSDate object.

• You may want to use timestampSerializer & timestampDeserializer if your metadata is simply an NSDate.
  **/

• (YapDatabaseSerializer)timestampSerializer;

• (YapDatabaseDeserializer)timestampDeserializer;