On 5/19/2014 11:54 AM, Joe Darcy wrote:
http://cr.openjdk.java.net/~darcy/8042864.0/src/share/classes/javax/print/attribute/standard/DialogTypeSelection.java.sdiff.html
< 113 public final Class getCategory() {
> 113 public final Class<DialogTypeSelection> getCategory() {
getCategory() is a super-class method ..
So this seems wrong to me and I think|it should look like this ..|
http://docs.oracle.com/javase/8/docs/api/javax/print/attribute/Attribute.html
|Class
<http://docs.oracle.com/javase/8/docs/api/java/lang/Class.html><?
extends Attribute
<http://docs.oracle.com/javase/8/docs/api/javax/print/attribute/Attribute.html>>|
|getCategory
<http://docs.oracle.com/javase/8/docs/api/javax/print/attribute/Attribute.html#getCategory-->()
|
Part of the generics language feature was covariant overrides, that
is, when a subtype overrides a methods from a supertype, the return
type of the subtype method can be a more-specific type.
That is the case here; DialogTypeSelection is a subtype of "? extends
Attribute" so the getCategory method in DialogTypeSelection is a
covariant override of the superclass method. Moreover, since the
superclass uses the "? extends Attribute" wildcard, the intention is
for subclasses to override this method when possible.
1. FYI it appears I reviewed the .0 version since the reference to the
.1 was so far down I didn't see it
2. I hadn't noticed until now that Henry also mentioned the
getCategory() API ..
3. The 64 (!) other peer subclasses all use Class<? extends Attribute>.
Yes, it will be a DialogTypeSelection but the primary use case is to
be a member of a
collection of Attribute so a more specific API type isn't very
useful at all .. and it
will just stick out like a sore thumb.
-phil.
