Applet Error

Question

Hi Experts,
        We have Migrated code from 11.5 to 12.0 but some times the applet's are not loading properly i am getting error like Error Loading Applet.if i run the page second time its working properly so what could be the problem ......Kindly help me out for fixing this issue.
Regards,
Shaan...

Answer 1

The null pointers you are gettings quite often come from attempting to reference applet methods like .getQueryObject or .getChartObject before they are ready for scripting.
Based upon your description of the problem in your initial forum post I would speculate that it's not 12.0 or the applets, but more than likely due to javascript on your page.  For an applet to work inconsistently or sporadically it is typically due to timing issues that are outside the control attempts to man-handle the applets on a page with client-side script.  An applet merely wants to query the server for knowledge of its underlying query and display templates, and when it has this information it runs the query and displays the results, so within a browser session where the client JRE has cached the knowledge of the QT and DT it just needs to request the data and display it.
Warning signs of this will be a body onLoad tag that reference an applet(s) or some sort of initialize function that attempts to force loading of the page in a particular order or progression (like would make more logical sense in server side programming).  Initial page loading and timing issues will haunt pages developed like this, and the numerous variables involved on the client environment tend to make things difficult to troubleshoot with some of the apparent guesswork evidenced in this thread.
To test this simply isolate one of your single applets onto a single test page by itself and see if it consistently loads properly.  If you have difficulties doing this because of too much script or dependencies between multiple applets, then you may be understanding the problem a little bit more than before.
Regards,
Jeremy