Meet Error when run Spring MVC web application, " Servlet [mvc-dispatcher] in web application threw load() exception java.lang.ClassNotFoundException"

Hello I was trying to build a simple spring MVC project but when I am running my code I am getting: Hello I am new to spring and I was trying to build a simple spring MVC project but when I am running my code I am getting: Servlet [mvc-dispatcher] in web application threw load() exception java.lang.ClassNotFoundException

I run it in Eclipse + TomCAt 9.0