Dynamic Web Module facet version问题

index.php/tags-41973.html" >The default superclass, "javax.servlet.http.HttpServlet", according to the project's Dynamic Web Module facet version (3.1), was not found on the Java Build Path.

1.右键项目

2.点击Properties

3.点击Java Build Path，右边找到Libraries，下面点击JRE System Library，右边点击Edit，将JRE改为自己的