Data Lazy Loading

1. Determine if the data set is empty, and if the data is loaded empty, you do not need to load the data.

-(Nsarray *) roles{if(_roles = =Nil) {
Get data file NSString*path = [[NSBundle mainbundle]pathforresource:@"heros.plist"Oftype:nil]; Nsarray*array =[Nsarray Arraywithcontentsoffile:path]; Nsmutablearray*mutablearray =[Nsmutablearray array]; Fetch Data for(Nsdictionary *dicinchArray) {roleentity* Role =[roleentity Rolewithdictionary:dic];        [Mutablearray Addobject:role]; } _roles=Mutablearray; }    return_roles;}

Data Lazy Loading