OC高效率52之经过协议提供匿名对象

#import <Foundation/Foundation.h>
@protocol EOCDatabaseConnection
-(void)connect;
-(void)disconnect;
-(BOOL)isConnected;
-(NSArray*)performQuery:(NSString*)query;
@end

/**
 *  能够用协议把本身所写的API之中的实现细节隐藏起来，将返回的对象设计为听从此协议的纯id类型，想要隐藏的类名就不会出如今API中了
 */
@interface EOCDatabaseManager : NSObject
+(id)sharedInstance;
-(id<EOCDatabaseConnection>)connectionWithIdentifier:(NSString *)identifier;
@end


@implementation EOCDatabaseManager

@end