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Calling Win32 ShowWindow from Java/JACOB

mdsrobbins asked
Medium Priority
Last Modified: 2013-12-22
I'm seeking to call the Windows ShowWindow service from Java via JACOB to restore/minimise a Window of a given title but can't find any examples of doign this.  Can someone provide an example or an alternative means to achieve the same end.
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Top Expert 2004
Not sure why this is tagged as Groovy, but here goes...

I couldn't find a JACOB example (as they seem to have decided to move their wiki to SF, and not put any documentation up), but I found this library here:


Now, I've never used JNative, but the how-to (showing how to set it up) seems to be here:


And it looks like you should be able to do the following...

(maybe -- I haven't tried, and I'm not on Windows)

HWND hwnd = org.xvolks.jnative.util.User32.findWindow( null, "Window Title" ) ;
org.xvolks.jnative.util.User32.showWindow( hwnd, org.xvolks.jnative.misc.MSG.WindowsConstants.SW_MINIMIZE ) ;

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Thanks - the code works though as you say it is not JACOB based.  

I have also located serveral other libraries that provdie similar "native" access.  Anyone interested in alternatives should look at the following website:


I would, however, prefer a JACOB based solution if one exists.  The problem is that JACOB appears to need you to supply a CLSID or PROGID for the library for which it looks up the Registry etc to locate the DLL etc and there does not *appear* to be one for User32.dll.



I have had confirmed elsewhere that in fact user32 and other low-level calls in kernel32 etc are NOT COM based services and therefore JACOB cannot be used so JNative or other direct call libraries is the only approach I'm aware of.
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