Running the Servlet

With the Java Web Server, servlets are placed in the servlets directory within the main JWS installation directory, and are invoked via http://host/servlet/ServletName. Note that the directory is servlets, plural, while the URL refers to servlet, singular. Since this example was placed in the hall package, it would be invoked via http://host/servlet/hall.HelloWorld. Other Web servers may have slightly different conventions on where to install servlets and how to invoke them. Most servers also let you define aliases for servlets, so that a servlet can be invoked via http://host/any-path/any-file.html. The process for doing this is completely server-specific; check your server's documentation for details. 

    source : http://www.apl.jhu.edu