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

Overview and Architecture
NonStop Servlets for JavaServer Pages (NSJSP) System Administrator’s Guide—525644-002
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JavaServer Pages (JSP)
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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
JavaServer Pages (JSP)
JavaServer Pages (JSP), a presentation-layer technology that sits on top of the Java
servlets model, simplifies the creation and management of dynamic HTML. JSP uses a
component-based rather than a page-based approach to development. In page-based
Figure 1-1. A J2EE Web Container With Two Applications
VST901.vsd
WEB CONTAINER
APPLICATION # 2
JAVA
SERVLETS
DEPLOYMENT
DESCRIPTOR
JAVA
CLASSES
JSP
PAGES
APPLICATION # 1
JAVA
SERVLETS
DEPLOYMENT
DESCRIPTOR
JAVA
CLASSES
JSP
PAGES