On 6/11/06, James M Snell <[EMAIL PROTECTED]> wrote:
The generics are an API optimization. The code autodetects what is
being parsed. In every case, Document.getRoot() returns some derivative
of the FOM Element interface. If you know what you're parsing, use the
generics; if you're not sure what you're parsing, don't use the generics
and do an instanceof to see what you ended up with. I'm not sure I see
the "problem".
Using instanceof can fail if the object you are testing was created via a
different instance of the class than the one you are comparing it to (i.e.
when multiple class loaders are in play). Is that a non-issue here, somehow,
or do we need to guard against it?
--
Martin Cooper
Alternatively, plug in an Atom 0.3 Extension Factory and provide a set
of classes that implement the FOM on top of the Atom 0.3 model. Then
you could continue to use the generics form. By Tuesday I should be
able to post some sample code that illustrates this...
Document<Feed> doc = Parser.INSTANCE.parse(atom03FeedStream);
Feed feed = doc.getRoot();
System.out.println(feed.getClass()); // outputs sample.Atom03Feed
- James
Garrett Rooney wrote:
> On 6/10/06, James M Snell <[EMAIL PROTECTED]> wrote:
>> Abdera will successfully parse any well-formed XML. The trick is not
to
>> use generics when parsing.
>>
>> Document doc = Parser.INSTANCE.parse(someInputStream);
>>
>> The parser will automatically detect whether the XML stream is an Atom
>> document (Feed, Entry or Atom Publishing Protocol Introspection doc) or
>> whether it is some other XML.
>>
>> Element element = doc.getRoot();
>>
>> if (element instanceof Feed) {
>> // it was an Atom Feed document }
>> if (element instanceof Entry) {
>> // it was an Atom Entry document }
>> if (element instanceof Service) {
>> // it was an APP Introspection document }
>> if (element instanceof ExtensionElement) {
>> // it was arbitrary XML }
>>
>> More below.
>
> Makes one wonder what the point of the generics is, if you can't use
> them if you want to be able to recover gracefully from such
> problems...
>
> -garrett
>
