NonStop Servlets for JavaServer Pages (NSJSP) 6.0 System Administrator's Guide

Overview and Architecture
NonStop Servlets for JavaServer Pages (NSJSP) 6.0 System Administrator’s Guide—544548-004
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Implementation of NonStop-specific features in
NSJSP 6.0
Implementation of NonStop-specific features in NSJSP 6.0
In NSJSP 6.0, changes to the Tomcat 6.0.13 code is kept at a bare minimum. This is
done to facilitate easy migration to newer releases of Tomcat. To implement NonStop-
specific features, suitable configuration plug-in points are identified. Wherever changes
to Tomcat 6.0.13 code changes are imperative, the changes done preserves the
default Tomcat behavior while implementing NonStop-specific behavior.
The following is an example where a configuration plug-in point is used to introduce
Non-Stop specific feature:
Feature description: NSJSP requires all applications to use a Non-Stop specific
session manager (NSJSPStandardManager) instead of the default session manager
(StandardManager) provided by Tomcat.
Feature implementation in NSJSP 6.0: Unlike the earlier releases, there are no code
changes done to Tomcat 6.0.13 to implement this feature. Instead, a NonStop-specific
class NSJSPStandardManager is written, which has a NonStop-specific functionality.
NSJSP 6.0 ensures that all applications use NSJSPStandardManager as the default
session manager by configuring the Manager element in the conf/context.xml file.
The following is an example where the Tomcat code has been modified to implement
an NSJSP functionality:
Tomcat, by default, obtains all the data from a TCP/IP port. This default behaviour is
changed in NSJSP 6.0 such that the NSJSP server receives data from the HTTPD
process intead of the TCP/IP port. This change in the default behaviour is achieved by
modifying the ServerSocketFactory class of the connector component in Tomcat.
The change, however, retains the ability of the server to process request from TCP/IP
ports too. The switch in the behaviour of the server can be made by using certain
configuration parameters.
Comparison between NSJSP 5.0 and NSJSP 6.0
This subsection provides an overview of the similarity and difference between NSJSP
5.0 and NSJSP 6.0.
NSJSP 6.0 retains all the core NonStop components of NSJSP 5.0. For example, the
connector libraries are reused in NSJSP 6.0 (with some modifications), to fit the
NSJSP 6.0 internal code infrastructure. Although there are internal code changes,
most of the features like Persistence Manager and NonStop JAAS Login of NSJSP 5.0
are retained in NSJSP 6.0.
The differences between NSJSP 5.0 and NSJSP 6.0 are because of the inherent
differences in their Tomcat counterparts. For example, the directory structure and the
logging configuration of NSJSP 6.0 is different from NSJSP 5.0.