Your web request is not looking for the .java file, rather its looking for the .class file. The folder for source(.java) might differ in different
IDE. However the .class files for any web application always goes under WEB-INF\classes. What does your form action say?
In a web application the directory structure goes some what like this
context root folder -> typically contains the static contents like html,gif,jpg etc.
context root folder\WEB-INF- typically contains the descriptor file like web.xml
context root folder\WEB-INF\classes - contains the .class files like servlet, beans.
context root folder\WEB-INF\lib - contains third party runtime libraries for e.g. 3rd party jar files.