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https://issues.apache.org/jira/browse/LABS-161?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12632015#action_12632015
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Simone Gianni commented on LABS-161:
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Also, quickly, the Handler uses getMethods .. it will return all methods, both
those declared on the target class and on superclasses, so it currently
"happens" that the method (generic) in the superclass is returned BEFORE the
specialized method in the subclass. This makes also the "manual subclassing" a
mess, but it is easily avoidable.
> WEB : Wise reflection for generic handlers
> ------------------------------------------
>
> Key: LABS-161
> URL: https://issues.apache.org/jira/browse/LABS-161
> Project: Labs
> Issue Type: Improvement
> Components: Magma
> Reporter: Simone Gianni
> Assignee: Simone Gianni
>
> It would be nice to be able to define generic web handler and generic beans,
> the define non generic subclasses, and have Magma behave correctly with them.
> Magma uses reflection/introspection to determine data types in a number of
> situations :
> * Examining the type of properties in a bean to setup proper conversion
> * Examining the parameters of a do or handle method in a webhandler to
> perform proper conversion
> If a generic handler is defined, and then a non generic but parametrized
> subclass is defined, this subclass is, formally, using concrete classes and
> not generics.
> Suppose the following :
> public class DisplayingBeanHandler<T> extends WebHandler {
> public HtmlProducer doShow(T bean) {
> ...
> }
> }
> public class DisplayPersonHandler extends DisplayingBeanHandler<Person> {}
> DisplayPersonHandler? has a doShow(Person) method, at any effect.
> Unfortunately, to keep compatibility, the Java compiler will instead create a
> synthetic method based on Object :
> public class DisplayPersonHandler extends DisplayingBeanHandler<Person> {
> // Injected by compiler
> public HtmlProducer doShow(Object bean) {
> super.doShow((Person)bean);
> }
> }
> While this ensures proper checks, reflection will see this method as using
> Object, so Magma will not know what to convert it to.
> Where this happen, Magma has to correctly check for generics, and behave
> correctly.
> Since there are many places (and many more in the future) requiring this kind
> of functionality, a small "library" should be created to ease this pain.
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