Re: [Resteasy-developers] IIOImageProvider and new bug

[Bill B. <bb...@re...>]

Ryan J. McDonough wrote:
> Yeah, I was planning on doing that as well, just not right away because 
> there's a few things I want to do. But I came across something that i 
> don't thing the spec supports: proving hints to providers.  Currently, 
> the provider will always use the highest quality settings for images 
> that can be compressed. However, if I want to use a lower setting 
> there's not a good way to configure that. You could configure this at 
> the application level, but if I want to different configurations for 
> different resources, there's not a portable way to do it.
> 
> This is an item that will also affect a FileProvider as well: where do 
> you read and write the files. The Jersey FileProvider uses temp files 
> which isn't very flexible. If I were writing files, I'd want to specify 
> a specific location. With that said, I was thinking about something like 
> this:
> 
>     @POST
>     @ConsumeMime("*/*")
>     @ProviderHints(provider = FileProvider.class,
>            hints= {@Hint(name="basedir",value="/opt/files")})
>     public File processFile(File file) {
> 
> To define the root location for this resource. With this approach, each 
> resource could write files to different locations. For the 
> IIOImageProvider, you could do something like this to change the 
> compression level.
> 
>     @POST
>     @ConsumeMime("image/*")
>     @ProduceMime("image/jpeg")
>     @ProviderHints(provider = IIOImageProvider.class,
>           hints= {@Hint(name="compresionQuality",value="0.6")})
>     public IIOImage transcodeImage(IIOImage image) {
> 
> In this case, we'd be overriding the default compression value to get a 
> more compressed image. There's still more thinking to be done, such as 
> is this just a class-level or method level annotation, etc. However, i 
> wanted to get some feedback on the idea.
> 

You don't need a @Hint in this case.  Just create a new IIOImage 
specific annotation

@POST
@ConsumeMime("image/*")
@ProduceMime("image/jpeg")
@CompressionQuality(0.2)
public IIOImage transcodeImage(@CompressionQuality(0.6) image) {...}


The @CompressionQuality annotation would be 0.6 for the 
MessageBodyReader, 0.2 for Writer.

You get the list of annotations on the parameter for input, method for 
output.

-- 
Bill Burke
JBoss, a division of Red Hat
http://bill.burkecentral.com