On Tue, Jan 25, 2011 at 12:31 PM, Greg Brown <[email protected]> wrote:
> > I think you do not write Java code using these API directly(relying on
> BXML), you would think the casting is not big deal.
>
> These APIs are typically used from code, not BXML - I just don't think that
> casting is a big deal in general. Sometimes it is necessary, especially when
> APIs are designed to be generic (like this one). But, like I said, it is
> easy enough to add a type parameter to the method to avoid the need to cast.
>
If the generic is something essential in the modeling, this type of cast
issue may be ignored.
But the use of anonymous type is just to accept some List<*> class as the
setter argument.
We may set different List<A.>, List<B> to the same instance of A, also we
may add any type of object.
A is designed to hold just List<Object>.
If we consider this way, enforced cast is very technical thing, should be
avoided.
Also the intended cast to List<J> is not type safe anyway. So such usage
itself is a bit tricky, maybe deserve for double
casting.(or getList(Class<T> cls).
The one suggested clint will not allow simple getList as default. List<?>
_getList() may be supported for a bit safer casting.
'A' should be implemented this way, avoid anonymous type in instance
property:
static class A {
List<Object> ts;
// new version
public List<Object> getList() {
return ts;
}
public <T> List<T> getList(Class<T> cls) {
return (List<T>)ts;
}
public <T> void setList(List<T> ts) {
this.ts = (List<Object>)ts;
}
public List<?> _getList() {
return ts;
}
public void setList1(List<?> ts) {
this.ts = (List<Object>)ts;
}
}
>
> > If you don't like to have two methods, it may just support List<Object>
> version. anyway we can alway cast to any type with double cast!
>
> Blech! That's even worse. :-)
>
>
>
>
--
Cheers,
calathus
