Free Support Forum -

[Java] Duplicated pages with ViewerHtmlHandler and cache


Group Docs Viewer for Java v17.2.; Windows 7; Java 1.7.0_79; apache-tomcat-7.0.56; Eclipse + Gradle

My little program will directly output PPTX html to browser as below codes:

  List<PageHtml> list = handler.getPages(filePath, o);
  for(PageHtml page : list)

When go to browser first time, the web page result looks OK like this: Normal_web_page_result.png (111.3 KB)

But when I pressed F5 or CTRL+F5 to refresh web page, the web page will show duplicated PPTX pages, like below:
Duplicated_pages_Chrome.png (72.8 KB)
Duplicated_pages_IE.png (94.5 KB)
And it won’t be fixed after keep refreshing web page.

I directly opened the html file in cache by browser, and the generated html file does show duplicated pages. (232.6 KB)

That’s weird. Why two same pages are generated?

I attached my Eclipse project for you to reproduce problem: (70.2 KB) (2.5 MB)
You need to modify some paths in code.

Thanks for any comments.

Thanks for trying GroupDocs.Viewer for Java and posting your concerns.
We shall configure the environment, investigate your issue and let you know about the outcomes.


We successfully reproduced this issue at our end. Following are the basic reasons:

  • You are evaluating API in trial mode
  • The document you are rendering is a large document (38 slides). So, when you are in trial mode documents with more than 2 pages are not processed properly
  • See further API limitations when it is evaluated in trial mode

But the good thing is you can request a temporary license here. This temporary license will permit you to avail all the API functionalities for a restricted period of time. We’d suggest you to request a temporary license, try to render documents again and share your experience.