On 22.11.2013 00:15, Phil Race wrote:
The other problem you mention is largely if not entirely because IPP
lumped
trays along with papers as being "Media".
See http://tools.ietf.org/html/rfc2566#section-4.2.11
If a Printer object supports a medium name as a value of this
attribute, such a medium name implicitly selects an input-tray that
contains the specified medium. If a Printer object supports a
medium
size as a value of this attribute, such a medium size implicitly
selects a medium name that in turn implicitly selects an input-tray
that contains the medium with the specified size. If a Printer
object supports an input-tray as the value of this attribute,
such an
input-tray implicitly selects the medium that is in that input-tray
at the time the job prints.
If I understand this correct, that means it should be possible to
just define a MediaTray without a MediaSizeName then right? But in my
environment the default MediaSizeName is set to Letter even though
the current PrintService would define A4 as the default.
I see a line in RasterPrinterJob.java which might cause that to happen
if you specify
a tray and no paper but that seems like its a bug. It should always be
the default for the current
printer unless I'm forgetting something we had to do for backwards
compatibility.
Do you mean this lines starting at 562:
Media media = (Media)attSet.get(Media.class);
if (media == null) {
media =
(Media)service.getDefaultAttributeValue(Media.class);
}
if (!(media instanceof MediaSizeName)) {
media = MediaSizeName.NA_LETTER;
}
This would replace a set MediaTray from the attribute set with the
MediaSizeName.NA_LETTER right? A would sugest to change the lines to
something like this:
Media media = (Media)attSet.get(Media.class);
if (media == null) {
media =
(Media)service.getDefaultAttributeValue(Media.class);
if (media == null) {
media = MediaSizeName.NA_LETTER;
}
}
This would fall back to letter in case of a non default definition of a
media size name and no such is defined within the request attributes...
If I compare the basic behavior in comparison to the Windows
implementation. The are some differences in setting the default
MediaSize and MediaSizeName. Those will be not initialized in the
Windows world and taken from the current PrintService in case it's
not set via PrintRequestAttributeSet.
I can see no way around this other than defining an new attribute
class that doesn't
subclass Media and duplicates MediaTray .. but then you'd also need
to say what happens
if someone specifies two different trays, one by each means.
I do not completely understand what you mean. Do you mean the use
case if one specifies A4,Tray2 but Tray2 contains Letter?
I meant that if we provided a new class "MediaSource" you could
specify MediaSource.TRAY1
whilst still specifying for "Media" an instance of the subclass
MediaTray that corresponded
to TRAY2. That's an API solution that doesn't seem likely any time soon.
I always thought that the MediaTray does specify the source already as
it says in the JavaDoc:
"*IPP Compatibility:* MediaTray is a representation class for values of
the IPP "media" attribute which name paper trays. "
In newer Printer there is also the possibility to specify the output
tray as well but for this there is no specific definition within the spec.
Cheers
Patrick
