Whacky XML editor in Intellij IDEA

[Oleg Tkachenko <oleg@tkachenko.com>]

Hello!

Talking about namespaces - surprisingly I found out there is a growing 
amount of developers who truly believe any namespace URI in a XML 
document must be resolvable to a schema document and otherwise XML 
document isn't valid.

After some hot debates I found out the root of this belief is whacky 
behaviour of (new?) Intellij IDEA's XML editor.
I just installed fresh IDEA release, created new XML file and typed
<foo xmlns="http://whacky.com"/>
IDEA markes this line as error, highlighting "http://whacky.com"; in red 
and tooltiping "URI is not registered (Settings | IDE Settings | 
Resources)". That means I supposed to go to Resources dialog and either 
add http://whacky.com to the list of ignored external resources or to 
map it to a local XML schema file.

I googled out a thread in IDEA support forum [1], where they defend this 
behaviour, referring to the section 4.3.2 of the "XML Schema Part 1: 
Structures" [2], which particularly says:

"Note:  Experience suggests that it is not in all cases safe or 
desirable from a performance point of view to dereference namespace 
names as a matter of course. User community and/or consumer/provider 
agreements may establish circumstances in which such dereference is a 
sensible default strategy: this specification allows but does not 
require particular communities to establish and implement such 
conventions. Users are always free to supply namespace names as schema 
location information when dereferencing is desired: see below."

and:

"Given a namespace name (or none) and (optionally) a URI reference from 
xsi:schemaLocation or xsi:noNamespaceSchemaLocation, schema-aware 
processors may implement any combination of the following strategies, in 
any order:
...
5 Attempt to resolve the namespace name to locate such a resource."

So they believe that's just fine and conformant.

Now while it's weird for me when XML editor forces me to resolve 
namespace URI, apparently many Java devs working in IDEA (which is quite 
popular IDE) take it as granted.
Can we (and should we) do something about it?


[1] http://www.intellij.net/forums/thread.jsp?forum=5&thread=2021
[2] http://www.w3.org/TR/xmlschema-1/#schema-loc
-- 
Oleg Tkachenko
http://blog.tkachenko.com
Multiconn Technologies, Israel