<p>I have a Java desktop application that uses the BIRT 4.3.2 runtime to generate reports, and have run into an issue with a class file signature mismatch that I believe is at least related to the one identified here: <a data-ipb='nomediaparse' href='
https://bitbucket.org/yaytay/spudsoft-birt-excel-emitters/issue/136/error-with-class-orgapachepoipoidocument-s'>https://bitbucket.org/yaytay/spudsoft-birt-excel-emitters/issue/136/error-with-class-orgapachepoipoidocument-s</a></p><p> </p><p>The reason I say "related" is that I'm not trying to use any emitters other than those included with the BIRT runtime itself, and I haven't seen anyone report this problem occurring in that particular context, let alone a resolution for someone in my situation. Through trial and error I determined that the XLSX emitter is the culprit, as I don't run into the '<em>"org.apache.poi.POIXMLDocument"'s signer information does not match signer information of other classes in the same package</em>' error as long as I stay away from that one emitter. For the time being I'm simply making that emitter unavailable to my users. Since it's not one they're expecting to have anyway, it's not a major problem for me at the moment, though I would like to make it available someday.</p><p> </p><p>Based on what I've read and the error messages I'm seeing, I think the issue is that there is a mismatch between <em>POIXMLDocument.class</em> found in <em>org.eclipse.birt.runtime_4.3.2.v20140225-1404.jar</em> and <em>POIDocument.class</em> found in <em>org.apache.poi_3.9.0.v201303080712.jar</em>, both of which are included in the BIRT 4.3.2 runtime.</p><p> </p><p>I've seen references to something called Maven as well as POI and OSGi in the discussions surrounding this issue. While I've encountered mentions of these items in past travels, I don't have a good idea what exactly they are, let alone any experience actually trying to use any of them (at least knowingly). If someone could provide or point me to a 10,000 foot view of any of those technologies it would be much appreciated. I would also appreciate any vectors to information that might address my current dilemma. Thank you.</p>
