Mapping in web.xml is what i have done :-
packagename.filename between opening and closing of servlet-class tag in xml file.
Both methods dont work with one another , so either i use annotation method of files mentioned when we create servlet or the way of mapping , then i delete or comment the annotation line. Eg:
<servlet>
<servlet-name>s1</servlet-name>
<servlet-class>performance.FirstServ</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>s1</servlet-name>
<url-pattern>/FirstServ</url-pattern>
</servlet-mapping>
<servlet>
<servlet-name>s2</servlet-name>
<servlet-class>performance.SecondServ</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>s2</servlet-name>
<url-pattern>/SecondServ</url-pattern>
</servlet-mapping>
Commenting the annotation line of code in the respective file,if mapping in xml is done.
//@WebServlet("/FirstServ")
//@WebServlet("/SecondServ")