Re: Generics headache
Lew wrote:
I was asking for your insight in how to do the refactoring...
Chuck la Salle wrote:
But of course!
Currently, we have something like (but only 'like'):
abstract class Parser<T> {
public abstract AST parse(Scanner scanner) ;
public abstract void doAfterEachMatch(T value) ;
}
abstract class InterceptableParser<T> extends Parser<T> {
// there isn't actually any foo, but YKWIM
// the actual code is a bit too complicated to reproduce
public void foo(T value) {
this.doAfterEachMatch(value) ;
}
}
I would refactor to:
abstract class Parser {
public abstract AST parse(Scanner scanner) ;
}
abstract class ActionAfterMatchParser<T> extends Parser {
public abstract void doAfterEachMatch(T value) ;
}
abstract class InterceptableParser<T> implements ActionAfterMatchParser<T=
{
public void foo(T value) {
this.doAfterEachMatch(value) ;
}
}
I'd also change the purely abstract classes to interfaces.
Beautifully done.
--
Lew
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