Abstract class

[Anukool Rege <AR...@Scient.com>]

I have an abstract class in one of the methods signature-

placeOrder (Security in0, quantity in1, tradeType in2, price in3) where
Security is an abstract class. The concrete classes that extend Securities
are Stock, Bond and Mutual Fund.

I have noticed that the WSDL2Java generated bindings always pick Stock as
Security replacement. 
 interface definition of the same method reads - placeOrder(Stock in0,
quantity in1, tradeType in2, price in3)

Is there any logic behind the choice of concrete class? Why does it pick
stock and not bond? or why not generate three methods for each concrete
type?

Thanks,
Anukool Rege