[jaxrs-cxf-cdi] multipart file upload should only present Attachment

[selliera]

Current template in case of a multipart file upload, will provide both Attachment and InputStream arguments.
The InputStream is not necessary, as it can be obtained from the Attachment object via getInputStream().
Moreover, when the API provides both, it becomes hard for implementers to know what to do: if using only the Attachment, should they close the input stream.
Providing only the Attachment, and using it to obtain the InputStream makes things easier to read/understand.

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[wing328]

thanks for the pr

we will consider this a bug fix, and let's see if anyone needs the input stream for whatever reason.

[selliera]

Thanks !
For the record, the change to apply to application code that was previously using the InputStream instead of the Attachment will be like changing:

try (inputstream) {
  // processing
}

with

try (attachment.getDataHandler().getInputStream()) {
  // processing
}