[Eclipse]错误:The superclass "javax.servlet.http.HttpServlet" was not found on the Java Build Path

Eclipse error
When importing an existing Dynamic Web app project, an error message appears in the jsp page code:
The superclass "javax.servlet.http.HttpServlet" was not found on the Java Build Path
Solution: Build Path > Configure Build Path > libraries > Add Libraried > Server Runtime > tomcat; Order and Export > Check Apache tomcat