Jolt 1.2 Developer's Guide

8.
Using Servlet Connectivity for NonStop
TM
TUXEDO
With Compaq NonStop
TM
TUXEDO Jolt 1.2 servlet connectivity, you can use HTTP servlets to perform server-side Java tasks in response
to HTTP requests. Remote Jolt clients previously were Java applets or applications that connected directly to the Jolt Server in order to
request NonStop
TM
TUXEDO services. Jolt 1.2 certifies pool with the Java Web Server Versions 1.1.3 and up, and supports most other
standard servlet engines. Using the Jolt 1.2 session pool classes, a simple HTML client can now connect to any web server that supports
generic servlets. Thus, all Jolt transactions are now handled by a servlet on the web server rather than being handled by a client applet or
application.
This capability means that HTML clients can invoke NonStop
TM
TUXEDO services without directly connecting to NonStop
TM
TUXEDO.
HTML clients can instead connect to a web server, via HTTP protocol, where the NonStop
TM
TUXEDO service request is executed by a
generic servlet. Using a Jolt session, the servlet on the web server administers the NonStop
TM
TUXEDO service request by connecting to the
NonStop
TM
TUXEDO Server via the Jolt Server Handler (JSH) or the Jolt Server Listener (JSL), which then makes the NonStop
TM
TUXEDO service request. This capability allows many types of HTML clients to make remote NonStop
TM
TUXEDO service requests. All
Jolt transactions are now handled on the server side without requiring any change to the original HTML client. Thus, HTML clients are
allowed to be very simple and require little maintenance.
This section covers the following topics:
What Is a servlet?●
How Servlets Work With Jolt●
Writing and Registering HTTP Servlets●
Jolt Servlet Connectivity Sample●
Additional Information on Servlets●
What Is a servlet?
A servlet is any Java class that can be invoked and executed on a server, usually on behalf of a client. A servlet works on the server, while
an applet works on the client. An HTTP servlet is a Java class that handles an HTTP request and delivers an HTTP response. HTTP servlets
reside on an HTTP server and must extend the JavaSoft javax.servlet.http.Http Servlet Class so that they may run in a generic servlet engine
framework.
Following are some of the advantages of using HTTP servlets:
They are written in a well-formed and compiled language (Java), so are more robust than "interpreted" scripts.●
They are an integral part of the HTTP server that supports them.●
They can be protected by the robust security of the server, unlike some CGI scripts that are hazardous.●
They interact with the HTTP request via a well-developed programmatic interface, and so are easier to write and less prone to errors.●
How Servlets Work With Jolt
With Jolt servlet connectivity, any generic HTTP servlet allows you to take advantage of the Jolt features. Jolt servlets handle HTTP
requests using the following Jolt classes:
ServletDataSet●
ServletPoolManagerConfig●
ServletResult●
ServletSessionPool●
ServletSessionPoolManager●
The Jolt Servlet Connectivity Classes
Following are descriptions of the Jolt servlet connectivity classes:
ServletDataSet