What do you mean by the "name" of your object?  If you
mean an instance member, e.g.

    class Stock {
       String name;
       ...
    }

... then just supply the name via whatever mechanism you've
already established: a Stock constructor, or a setName method,
or whatever.

   If you mean the identifier of the reference variable with
which you refer to a Stock object

    Stock bluechip = new Stock("WMT");

... then there's no way[*] to create a new `bluechip' at run
time based on the content of some file.  Besides, it's misleading
to think of `bluechip' as the "name" of the Stock; `bluechip' is
just a reference variable that might point to your Wal-Mart
stock at one moment and to your Enron stock the next.  And it
mightn't even be unique: What if you follow the above with

    Stock redchip = bluechip;
    Stock greenchip = redchip;
    Stock tacochip = greenchip;

?  It's clearly nonsensical to say that all of `bluechip',
`redchip', `greenchip', and `tacochip' are "the name" of your
Wal-Mart stock.

  [*] Actually, there *is* a way to create new reference
variables at run time, but you must give up some freedom in
the way you name them.  Here's how:

    int stocks_count = 42;  // or figure it out somehow
    Stock[] stocks = new Stock[stocks_count];

... and now you've got a whole bunch of references, named
`stocks[0]', `stocks[1]', and so on.  Or instead of an array
you could use a Collection object to hold "nameless" references
to your Stock objects:

    List stocks = new ArrayList();
    stocks.add(new Stock("WMT"));
    stocks.add(new Stock("IBM"));
    ...