NonStop Servlets for JavaServer Pages (NSJSP) 5.0 System Administrator's Guide

Overview and Architecture
NonStop Servlets for JavaServer Pages (NSJSP) System Administrator’s Guide—525644-003
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The Web Container
Dynamic content was initially supplied by CGI, but now the more powerful and flexible
Java Servlet API and JSP programs provide logic for the new web applications.
The Web Container
For building and running web-based applications, J2EE provides a web container,
which is a Java runtime environment that has the following content:
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The applications, including Java servlets and JavaServer Pages, class libraries,
resources such as HTML or XML documents, and images.
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The Servlet API and runtime management including initializing, invoking, and
managing the Servlet and JSP lifecycles.
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The deployment descriptors (the web.xml file) that contain resource definitions
such as MIME types, mapping of requests to servlets, access control, and servlet
initialization parameters.
The web container instantiates the servlet and provides the communication between
the iTP WebServer and the servlet. Specifically, the web container:
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Instantiates the servlet
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Invokes the servlet’s init() method
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Requests services from the user by invoking the service() method
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Invokes the destroy() method when the servlet is to be garbage-collected
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Manages a similar lifecycle for JSP files
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Deploys and creates WAR (web archive) files