Purging the jobs in Winspool

[badarolp]

To purge the jobs in the spool you have to make a Winspool.SetPrinter with PRINTER_CONTROL_PURGE, but there is no such method in JNA.

Can I implement that? Is there other way to clean up my printer spooler?

[wolftobias]

Have you seen this example?

https://github.com/java-native-access/jna/blob/master/contrib/w32printing/src/com/sun/jna/platform/win32/Win32SpoolMonitor.java

[badarolp]

Yes, i saw it. But it's just a status monitor of the spooler.
For now I'am calling a .exe c++ program that clean's the spooler for me, but it's not so elegant...

[matthiasblaesing]

I think this is perfectly doable - you'll have to wire up the necessary parts in Winspool.java:

https://github.com/java-native-access/jna/blob/master/contrib/platform/src/com/sun/jna/platform/win32/Winspool.java

The documentation is in MSDN:
https://msdn.microsoft.com/en-us/library/windows/desktop/dd145082%28v=vs.85%29.aspx

A few of the PRINTER_INFO structures are already bound, so they can be used as a basis. The constants for the commands need to be added as contants to the interface (PRINTER_CONTROL_*)

[badarolp]

Thanks @matthiasblaesing, I will try this.

[wolftobias]

You have to use this, https://docs.microsoft.com/en-us/windows/win32/printdocs/setjob Am 31.10.2019, 23:21, "Luís F." <[email protected]> schrieb: I need to be able to clean my printer spooler. There's any solution to help me? —You are receiving this because you commented.Reply to this email directly, view it on GitHub, or unsubscribe. [ { "@context": "http://schema.org", "@type": "EmailMessage", "potentialAction": { "@type": "ViewAction", "target": "#661?email_source=notifications\u0026email_token=AARFBWCYZRTZ2K7B6SHRPYLQRNLANA5CNFSM4CELHU6KYY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGOECZNVXA#issuecomment-548592348", "url": "#661?email_source=notifications\u0026email_token=AARFBWCYZRTZ2K7B6SHRPYLQRNLANA5CNFSM4CELHU6KYY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGOECZNVXA#issuecomment-548592348", "name": "View Issue" }, "description": "View this Issue on GitHub", "publisher": { "@type": "Organization", "name": "GitHub", "url": "https://github.com" } } ]

[tresf]

Hi, plan on adding the SetJob to Winspool. I will submit a PR soon.

I noticed that some constants in Winspool are of type short whereas others are of type int. This addition requires adding something like this:

    public static final short JOB_CONTROL_PAUSE = 0x01;
    public static final short JOB_CONTROL_RESUME = 0x02;
    // ... 0x03, etc... 

I believe the Win32 API defines most of these as DWORDS, but I'm having a hard time finding out which one JNA should be using, quoting Winspool.java:

// int
public static final short PRINTER_NOTIFY_FIELD_SERVER_NAME = 0x00;
// short
public static final short JOB_NOTIFY_FIELD_PRINTER_NAME = 0x00;

Which should the PR use? Perhaps a better question is, how should I know this for future PRs? Thanks in advance.

[matthiasblaesing]

If a constant is only used "as is" and the use sites are declared as short, than it makes sense to use short in the constant definition. In this case the two short examples are used in PRINTER_NOTIFY_INFO_DATA.Type, from my quick read the value is only used there. Using an int for the constant would mean, that a cast is necessary when setting type.

This is different when the constants define discreet values of a bitfield. In that case it is highly probable that you will "or" the values together and you'll need a cast anyway.

For JOB_CONTROL* I don't see a reason to make them short. The use site is the only type indicator and a DWORD is indeed best mapped to int.