Thank you. I will try to resolve the problem here before submit a sample application for you.
I mean if there’s no specific configuration for enabling logging of internal classes of GroupDocs, SQLite or OrmLite. For example, to enable logging of Atomikos library for log4j we have to put the lines described in http://www.atomikos.com/Documentation/ConfiguringTheLogs#Log4J. The log4j were extensively used to write the internal classes of Atomikos, but to enable logging we have to configure the properties file of log4j to enable the printing of it.
I figured out what was the problem. It’s a bug using Aspose PDF version 10.3.0. I had to change to version 9.7.1 to resolve it.
First, I could debug the code on Wildfly server to see where the code was hanging. It were on the ViewDocumentServlet, method AnnotaionHandler.viewDocumentHandler() like on the attached image. Unfortunately I couldn’t reproduce the problem on another environment. I tried to reproduce it on a machine of a coleague, which runs Linux Mint. We put the app on a WildFly server on domain mode, but the problem doesn’t occur.
The only thing I was sure was that the viewer worked on the production server few weeks ago. So I deployed a old version of the application to verify. And discovered that the problem occurred when I upgraded GroupDocs.Annotation from version 1.9.0 to 2.0.0. On that upgrade, the version of dependent libraries of Aspose were upgraded too. GroupDocs.Annotations depends on the following Aspose libraries:
I tried to use the application with a more recent version of Aspose PDF (10.4.0) and with an older, but with the same features (10.0.0), but the problem were still working. So, I tried with the last version before version 10.0.0 and it worked. I’m using Aspose PDF 9.7.1 now. The other default Aspose JARs needed to use GroupDocs.Annotations 2.0.0 were kept.
The hardest part to discover the cause of this problem were that PDFs that were once viewed on the Viewer before the upgrade of GroupDocs.Annotation hadn’t any problems to open on the viewer. So, when I upgraded to newer version of GroupDocs.Annotations I didn’t have problems with this files, because it were cached and I thought that the viewer were ok. The problem only occured with new files or pages never shown on the viewer.
I extremmely recommend that you inform your customers that they can be faced with this problem. It were very difficult to discover and find its cause. For now, I don’t use a feature that probably were introduced with Aspose PDF 10, but I don’t want to keep using an older library. Will you investigate this bug?
Hi, Evgen. The problem only occurs on Wildfly on Domain mode. I tried to reproduce it on another machine, but I couldn’t. When I can give you a step by step guide to reproduce the problem I will tell you. What I can tell now is that switching Aspose PDF to version 9.7.1 resolved my problem.