servletexception

java.lang.ClassCastException cannot be cast to javax.servlet.ServletException

I'm trying to deploy a java application to appspot (google appengine). I'm new to java, so bear with me. When I run the application locally from eclipse, it runs fine. After uploading it to google appspot, I get an error (only in one of the .jsp pages, other .jsp pages work fine). The error log says: Uncaught exception from servlet ...

Servlet Exception + Class Cast Exception + Glassfish + Netbeans + JPA Entities + Vaadin

Hi all, I get this error: StandardWrapperValve[Vaadin Servlet]: PWC1406: Servlet.service() for servlet Vaadin Servlet threw exception java.lang.ClassCastException: com.delhi.entities.Category cannot be cast to com.delhi.entities.Category when I try to run my webapps on glassfish v2. Category is a JPA entity object the offending code...

How do I replace ServletException after Tomcat 6.0?

Hey, guys. Newbie to tomcat/apache, java returner here. I'm trying to run th step-by-step example here (http://static.springsource.org/docs/Spring-MVC-step-by-step/part1.html). Unfortunately, I keep getting an error that says "The project was not built since its build path is incomplete. Cannot find the class file for javax.servlet...