URL, URI, Context Path, path info

Consider following servlet conf 

 <servlet>
        <servlet-name>NewServlet</servlet-name>
        <servlet-class>NewServlet</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>NewServlet</servlet-name>
        <url-pattern>/NewServlet/*</url-pattern>
    </servlet-mapping>

Now When I hit url http://localhost:8084/JSPTemp1/NewServlet/jhi it will invoke NewServlet as it is mapped with pattern.
here

getRequestURI() =  /JSPTemp1/NewServlet/jhi
getPathInfo() = /jhi

getPathInfo()

returns
a String, decoded by the web container, specifying extra path information that comes after the servlet path but before the query string in the request URL; or null if the URL does not have any extra path information

getRequestURI()

returns
a String containing the part of the URL from the protocol name up to the query string

Its very important to know how container picks a servlet from which web app .(means how it identify the correct web app and then correct servlet)

Since the request uri consist of three main parts
Context Path- this helps container to choose the correct web app
ServletPath-this helps container to identify correct servlet into the from the requested web app.
PathInfo-in case of directory match

So if the request uri is
http://server.com/MyApp/servlet/xyz ,the container will first look for a web app named MyApp if it exists then it will look for the resource(here servlet) mapped to /servlet/xyz.

In case if there is no web app named MyApp then it (Tomcat)will look into the default web app (ROOT) for the servlet mapped to the uri /MyApp/servlet/xyz and proceed acc to that.