Re: Instantiate an abstract class
Rob McDonald wrote:
Joshua Cranmer wrote:
Rob McDonald wrote:
Now, we all know that you can't instantiate an abstract class -- but I
want to anyway... Actually, I would like my abstract class to be able
to instantiate another instance of whatever concrete class it is at
the time.
Your class is abstract, so you can easily have:
abstract class AFoo {
public abstract AFoo makeInstance();
That worked great. I don't know why I hadn't come up with that
solution myself.
Most of my online searches had lead down the reflection path and I
quickly got myself wrapped around the axle. I'm going to go with the
above implementation, but I am curious about how it could be made to
work the other way.
Because you haven't yet read /Effective Java/ by Joshua Bloch. You must. We
all must, and not just once, either.
<http://java.sun.com/docs/books/effective/>
The very first item of which is,
"Item 1: Consider static factory methods instead of constructors"
--
Lew
Honi soit qui mal y pense.
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