Run-Time Session

1) The user accesses the URL that indicates that a Forms application should be run.
2) The Oracle HTTP Server receives an HTTP request from the browser client and forwards the request to OC4J (Oracle Containers for J2EE), because the /forms/frmservlet path matches the OC4J mount directive for the Forms Servlet in the fomrs.conf file. OC4J maps the request to the Oracle Forms application, whose context root is /forms. It maps the request to the Forms Servlet by using the servlet mapping frmservlet specified in the web.xml file.
3) The Forms servlet dynamically creates an HTML page containing all the information to start the Forms session. The Forms Servlet (running in OC4J) processes the request as follows:
a. Opens the servlet configuration file. If the configFileName parameter is not specified, the default configuation file forms/server/formsweb.cfg is used.
b. Determines which configuration section to use from the formsweb.cfg file. For example, if the URL contains the query parameter config=test, it uses the [test] section.
c. Determines which base HTML file to use, based on the type and platform of the browser that made the request and the settings of various parameters in to formweb.cfg file (specifically, baseHTMLjinitiator, baseHTMLjpi, and baseHTML)
d. Performs variable substitution in the base HTML file, as follows:
Whenever a variable (like %myParam%) is encountered, the Forms Sevlet looks for a matching URL query parameter (for example, &myParam=xxx). If there is no matching URL query parameterr, it looks for a mattching parameter in the formsweb.cfg file. If a matching parameter is found, the %myParam% varible is replaced with the parameter value.
e. Sends the contents back as an HTML page to the user's Web browser. Depending on which base HTML file the Forms Servlet selected, the HTML page sent back to Web browser contains an Applet tag, object tag, or an Embed tag to start up the Forms applet. The Forms applet runs in a JVM, either the Web browser's native JVM or a plug-in JVM (like Oracle JInitiator or Sun's Java plug-in). If the base HTML file selected was for a plug-in, and if the user does not already have that plug-in installed, the user is prompted to install the plug-in. In the case of JInitiator, the download location is under the virtual path /forms/jinitiator (a virtual path defined in the forms.conf file)

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