The compiler forces you to catch them.
Of course, but only exactly once at the end. How are the exceptions made
available to handle-errors at the moment? I guess somewhere in the tree
processor. So where is the problem letting it catch the exception? I still don't
see the need for the re-parenting.
No. Assuming there are several layers, currently the compiler forces you to catch the exception at every layer or declare it in the throws clause (which might be impossible if you're implementing an interface).
On the contrary, if PE extends RuntimeCascadingException, you have the freedom to catch it only in the outermost layer, that would probably be the sitemap processor. Or you can catch it wherever you like.
The conventional wisdom is that it's better to have the compiler remind you that you have to catch most exceptions, because that's part of the contract. My opinion, instead, is that checked exceptions are a very bad way of enforcing contracts between callers and callees.
This is where I don't follow you.
The conventional wisdom is also that strong type checking helps in enforcing contracts. Judging from the recent flourishing of untpyed or weakly-typed languages like Python, Ruby, Groovy or Javascript [1], I'd be inclined to doubt that wisdom too.
Same here. Do you remember this one: http://marc.theaimsgroup.com/?l=xml-cocoon-dev&m=107901388024464&w=4 ?? If I change the implementation to a Set the statement will fail. I need many more tests than with strong-typing. But the same way I do not want to care about request and form handling - I use an abstracting framework for it, and care only about business logic - I do not want to care about testing correct types. The only tests I want to write are about business logic.
What I hate in Java are untyped collections, that force me to cast when retrieving an object out of them, and long vs. Long (was it called auto-boxing?). Both will be fixed in Java 1.5 IIRC.
Joerg
[1] :
function myflow() { var obj = cocoon.getComponent(id); obj.someMethodThrowingCheckedException(); // What? No cast? No try-catch? Where's the compiler??? ;-) }
