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

Programming and Management Features
NonStop Servlets for JavaServer Pages (NSJSP) System Administrator’s Guide—525644-002
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Request and Response Streams
the data of the servlet. In most cases this arrangment is the most efficient method of
handling multiple requests for servlets that do not contain client data.
Be aware that multithreading may require you to allow for threading synchronization.
Every client has access to each field in the servlet: the fields of the servlet are being
shared by each client. If a field contains client-specific data, the access to that field
must be synchronized.
The SingleThreadModel interface has been deprecated in the Servlet 2.4
specification. You can achieve the same functionality using a singleton Java class.
Request and Response Streams
The CGI interfaces of the iTP Secure WebServer implement standard input and output
as streams. Therefore, the length of a request to or response from a servlet is
unlimited.
The NonStop system interprocess communications mechanism is not inherently
stream-oriented. The Pathway CGI interfaces simulate stream behavior by accepting a
series of interprocess messages as streams.
Security Considerations
You can use the Region directive to restrict access to a JSP or servlet by protecting
its URL. In addition, you can use Safeguard to restrict access to any disk, file, or
process on a NonStop system.
Beyond these rudimentary types of protection, all servlets are considered trusted. The
fact that all servlets must be loaded from the local iTP Secure WebServer environment
tends to limit, but does not rule out, breaches of security. Specifically, neither the iTP
Secure WebServer nor the NSJSP places any restrictions on what a servlet does,
beyond restrictions imposed by NonStop Server for Java.
The web container inherits the security attributes of the Pathmon environment.
International Character Set Support
The iTP Secure WebServer supports international character sets (Unicode) for input to
and output from the servlet environment. No specific configuration procedures are
required to use international character sets with servlets/JSP.
Caution. Exercise caution when you use TS/MP (Pathway) or iTP WebServer commands that
stop ServerClass executions in environments where threads are spawned from within the web
container. Stopping the web container immediately stops all execution threads that are running
within the web container. There are no runtime checks that allow the web container to stay up
and wait for all threads to finish running when a TS/MP (Pathway) STOP command has been
issued against the web container. If you stop the web container accidentally, restart the iTP
Secure WebServer environment or THAW,START the servlet server if you have issued the
FREEZE,STOP command.