Could some one please explain this java code for me. thanks

hopalong_ie wrote: »

Could some one please explain/comment this code for me, have uml exam tomorrow which includes some java, have spent two hours trying to understand this code.

public class Manager {
// This is declaring a variable that will hold a list of accounts.
// A vector is a synchronised implementation of java.util.List
private Vector theAccounts;

// This is a utility method that wraps the Vector's behaviour
public void addAccount (account acc) {
theAccounts.addElement (acc);
}

// Another utility method that wraps the Vector's behaviour
public void removeAccount (Account acc) {
theAccounts.removeElement (acc)
}
}
Thanks

I've added comments above.

This is actually pretty bad coding, they declare theAccounts as a Vector instead of a List or a collection, and then they use the legacy methods of addElement/removeElement. This code would have looked out of place in the late 90s. Also it's a pretty pointless attempt to add an unnecessary layer of abstraction, anyone who writes Java should know how to handle the default collections, and this was perhaps some sort of misguided attempt at replicating the compile time checks that are provided by generics.

All of the above code would be better expressed as such:

List<Account> accounts = new ArrayList<Account>();

The Manager class as it stands it completely redundant.

ronivek wrote: »

In addition your use of a collection is only applicable if the class is only ever going to be a collection of Account objects.

Which is exactly what the Manager class is trying to implement. Also it can probably be inferred from the name of the collection as well.

I'm pretty much going to go out on a limb here and say that it is code from an example question. My point remains it's anachronistic code, and it's use should be discouraged.