IntelliJ idea integrated Tomcat cannot find HttpServlet problem (June 13, 2015)

For the first time today, using IntelliJ idea to do something with Tomcat, after configuring Tomcat in IntelliJ, he started to write the servlet, but couldn't find the HttpServlet class because IntelliJ Idea does not automatically import the Servlet-api.jar package, we need to manually import, the following is the solution

The imported package can also be seen in the external libraries directory of the project after it is added.

IntelliJ idea integrated Tomcat cannot find HttpServlet problem (June 13, 2015)