RFR [JDK8]: 7169894: JAXP Plugability Layer: using service loader

[Joe Wang]

Hi Paul, Alan,

I'm back on this change.

On 6/25/2012 12:19 PM, Joe Wang wrote:
>
>
> On 6/25/2012 9:34 AM, Paul Sandoz wrote:
>> H Joe,
>>
>> I just focused on javax.xml.datatype and assumed the rest follows the 
>> same pattern :-)
>
> Yeah, they are mostly similar, except Schema and XPath that do a 
> little extra check.
>
>
I said too quick.  Yes, the steps are the same except for the validation 
and XPath.  But it happened that DatatypeFactory is the only one that 
had defined Exception in the 3rd step. All others were made to ignore 
any error, since in the regular JDK, we can always fall back to the 
default impl unless requested not to.

I've made all of the changes as we've discussed,  to catch the 
ServiceConfigurationError and pass on the cause for all of the 
factories/finders.  I wanted to post the change so that you could see 
them on Mon.  But I had to read the definitions again when I got to the 
SchemaFactory and noticed that it was the only one that did not have its 
own exception. Instead, it was defined to always throw IAE if no impl is 
available.

As I thought through these definitions, I felt I would probably change 
them back although I started to hate the tedious duplications as you 
expected :)   Indeed, I have to argue again, in the regular JDK, there's 
no need to catch any errors since they would be considered abnormal 
(Windows' blue screen came to my mind).  And in jigsaw, we shall only 
need to figure out a different error message when no provider is 
available, only if we wanted it to be more end-user friendly.

-Joe