Webrev for JAX-WS/JAXB/SAAJ services

[Paul Sandoz]

On May 17, 2012, at 7:07 PM, Jesse Glick wrote:

> On 05/17/2012 12:12 PM, Paul Sandoz wrote:
>> e.g. a default provider always occurs after any non-default.
> 
> Would seem simpler to not register this provider in module-info.java at all, and just use the simple idiom:
> 
> for (Service s : ServiceLoader.load(Service.class)) {
>  if (s.handles(arg)) {
>    return s.dealWith(arg);
>  }
> }
> // could of course also inline this code:
> Service s = new DefaultService();
> return s.dealWith(arg);


Good point. I was thinking it would be useful to capture simple idioms like this in ServiceLoader.

With lambda one could potentially do:

  ServiceLoader.load(Service.class).
    filter(s -> s.handles(arg)).
    getFirstOrElse(() -> new DefaultService()).  // this method does not currently exist in lambda
    dealWith(arg);

And with ServiceLoader:

  // Dunno if there is a short hand for referencing a constructor, DefaultService::?
  ServiceLoader.firstOrDefault(() -> new DefaultService()) 
  ServiceLoader.findOrDefault(s -> s.handles(arg), () -> new DefaultService())

Paul.