#import "TGDataItem.h" @interface TGDataItem () { NSMutableData *_data; } @end @implementation TGDataItem - (instancetype)init { self = [super init]; if (self != nil) { _data = [[NSMutableData alloc] init]; } return self; } - (void)appendData:(NSData *)data { [_data appendData:data]; } - (NSData *)data { return _data; } @end