well you rather know what getChildren returns, so you know what the
returned object is, like generally.
W dniu 12.01.2018 o 22:17, jeffrey kutcher pisze:
> The idea is not to be specific, but to be general. This is an example. In
> practice, I don't know what "o" is and so there has to be a discovery phase.
> I'm not sure how to make it more general than discovering the class via
> o.getClass(). As in this example, yes the class object returned is an
> ObservableList but I'm unable to add an object to this list via reflection.
> Why? And what can be done to change that? Why should it be changed? Because
> an object can be added to the list via vbox.getChildren().add(). Therefore an
> object should be permitted to be added via introspection. The avenue for the
> addition is different, the end result should be the same.
> There are lots of other classes in the Java libraries that have this same
> issue.
> There's also the issue of what gets returned can be many different types. How
> do you figure out which type should be returned? Not a trivial question; not
> so sure there's an answer. In this case, all I need is a List. Not an
> ArrayList, or an ObservableList, LinkedList, SortedList .... Please don't
> focus on this ... yet. Original issue first.
> On Friday, January 12, 2018, 1:25:13 PM CST, mandy chung
> <mandy.ch...@oracle.com> wrote:
>
>
>
> On 1/12/18 10:26 AM, jeffrey kutcher wrote:
>
> m = o.getClass().getMethod("add", new Class[] { Object.class, });
> o = m.invoke(o, new Object[] { button1, });
>
> o.getClass().getMethod(...) is an anti-pattern for finding a public method.
> Object.getClass() returns the implementation class while you want to invoke
> a public method `javafx.collections.ObservableList::add` in this case. In
> this case, the declaring class of the method is known and so one way to fix
> it is to use the specific Class:
> Class<?> observableListClass = javafx.collections.ObservableList.class;
> m = observableListClass.getMethod("add", new Class[] { Object.class, });
> o = m.invoke(o, new Object[] { button1, });
>
> Mandy
>
>
>
>
>
