Question

I am having problems with some course work i’m trying to finish off and any help would be appreciated!

I have 3 types of accounts which extend an abstract type “Account”.. [CurrentAccount, StaffAccount and MortgageAccount].

I am trying to read in some data from file and create account objects along with user objects to add to hashmaps stored within the program.

When I create account objects I use a temporary variable of type Account and define its subtype dependant on the data read in.

for example:

Account temp=null;

if(data[i].equalsIgnoreCase("mortgage"){
    temp= new MortgageAccount;
}

Problem is when I try to call a method belonging to type MortgageAccount..

Do I need a temp variable of each type, StaffAccount MortgageAccount and CurrentAccount and use them coresspondingly in order to use their methods?

Thanks in advance!

Answer 1

It depends. If the parent class Account has a method overridden in MortgageAccount, then when you call the method you’ll get the MortgageAccount version. If the method only exists in MortgageAccount, then you’ll need to cast the variable to call the method.