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From: Martin Gregorie on 12 Feb 2010 19:52
On Fri, 12 Feb 2010 18:45:32 -0500, Lew wrote:

> On 2/12/2010 6:13 PM, Daniel Pitts wrote:
>> There is Class.getResource*, but you probably want
>> ClassLoader.getResource*
>>
>> My understanding is that The Class.getResource looks in the same
>> package as the class, where ClassLoader.getResource looks relative to
>> the class-path roots which it knows about.
>
> See the link provided by John B. Matthews and the corresponding entry in
> the 'ClassLoader' Javadocs.
>
> The 'Class' version's behavior depends on the presence or absence of a
> leading '/' (slash) in the resource path. Without the leading slash,
> the resource is found relative the class's package, with the slash it's
> to the class path.

Thanks to all in this thread. I've made notes, read the docs for the
Class and ClassLoader methods and now think I know enough to do what I
wanted to do.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |
From: John B. Matthews on 12 Feb 2010 23:37
In article <hl4m2m$jkj$1(a)news.albasani.net>, Lew <noone(a)lewscanon.com>
wrote:

> Martin Gregorie <martin(a)address-in-sig.invalid> wrote:
> >> So the 'absolute path' takes the class's package as its root. Gotcha.
>
> John B. Matthews wrote:
> > Empirically, yes. It's my best interpretation of the getResource() API:
> >
> > <http://java.sun.com/javase/6/docs/api/java/lang/Class.html#getResource(java
..lang.String)>
>
> I think you have that backwards.
>
> AIUI, an absolute resource path (starts with '/') is relative to the class
> path, and a relative path (doesn't start with '/') is relative to the
> "modified_package_name".
>
> I am citing from the link provided. Plus, when I've run tests, I've observed
> behavior consistent with my interpretation.
>
> The wiggle room comes from
> "The rules for searching resources associated with a given class are
> implemented by the defining class loader of the class."
>
> So class loaders can change these rules.

You've elucidated a subtle point that I'd overlooked previously: The
leading '/' is a convenient notation in Class#getResource(); package
names don't have a leading '.' to modify. The corresponding method in
ClassLoader returns null when given a leading '/'.

--
John B. Matthews
trashgod at gmail dot com
<http://sites.google.com/site/drjohnbmatthews>
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