Q:

Is it possible to call a COM API from Java?

Is it possible to call a COM API from Java (specifically the HP/Mercury Quality Center OTA API)? If so, what's the best way?
Is something like JACOB appropriate?
Code fragments would be helpful for the basics :-)

A:

jacob : yes, http://sourceforge.net/projects/jacob-project/ is an active project that will suite your purpose pretty well.
you can see multiple examples : http://jacob-project.wiki.sourceforge.net/Event+Callbacks
but if you want something that is more tested and are willing to pay money, then go for http://www.nevaobject.com/_docs/_java2com/java2com.htm.

A:

after a comparison of all the above, none was totally satisfactory.
the most complete solution is in 
https://github.com/java-native-access/jna
now.
It supports,

getting interface to a running COM object
starting a new COM object and returning its interface 
calling COM methods and returning results
optional separate COM thread handling
ComEventCallbacks
RunninObjectTable queries
lowlevel COM use
util / high level java proxy abstraction

E.g.
MsWordApp comObj = this.factory.createObject(MsWordApp.class);

Documents documents = comObj.getDocuments();
_Document myDocument = documents.Add();

String path = new File(".").getAbsolutePath();
myDocument.SaveAs(path + "\\abcdefg", WdSaveFormat.wdFormatPDF);
comObj.Quit();

