Introduction to WebUtil

This manual documents the principals and usage of the WebUtil utility with Oracle Forms Applications. You should read and understand the sections on installing and configuring WebUtil before using the utility.

What Is WebUtil?

WebUtil is a pre-packaged set of components that can be used to add a great deal of extra functionality to Web-deployed Forms applications. WebUtil addresses common challenges faced by Oracle Forms developers who wish to build applications which integrate tightly with the client browser - the computer at which the end user is actually located.

Traditionally, Oracle Forms has provided the means of integration with the computer that the Forms executable is running on. However, in the Web-deployed scenario, the delivery of the Forms application can be remote from end users and may even be on a different operating system from the systems that are being used to host the application's user interface. WebUtil allows Oracle Forms developers the means to interact with the client browser computers by using PL/SQL, and without having to learn any new technology. As such, WebUtil is designed for programmers who are migrating client server applications from Microsoft Windows desktops to the Web, but still need some integration between their Oracle Forms applications and external packages such as the Microsoft Office Suite running on the client browsers' computers.

The Principles of the WebUtil Design

The aim of WebUtil is to provide a utility that any Forms developer can use to carry out complex tasks on the client browser computer by simply coding in PL/SQL. Although WebUtil itself uses Java extensively, there is no need for the developer to have any understanding of Java. Everything the developer needs to do is exposed through a standard PL/SQL library webutil.pll.All of the components that are needed to support WebUtil are likewise exposed through a simple object group.For an Oracle Forms application to take advantage of WebUtil, you only need to attach the WebUtil library and subclass the Object Group. No setup or configuration in code is required as WebUtil is self-configuring and where necessary, self-installing. Some features of WebUtil, such as client side OLE integration, require code to be installed onto each client computer. One of the key features of WebUtil is its ability to "self-install" in these cases. There is no need for an administrator to configure each and every computer because WebUtil detects which client-side pieces are missing and automatically installs them.Another aim of WebUtil is to simplify porting of client server integration code to work on the client browser computer. To achieve this, WebUtil contains PL/SQL APIs mimic the behavior of the equivalent native Forms functions.An example of this is the Forms TEXT_IO package. This package provides the developer with facilities to read and write text files on the application server. WebUtil provides an alternative implementation, CLIENT_TEXT_IO, which is identical to TEXT_IO except that calls are implemented on the client browser computer rather than on the middle tier. Migrating existing code to operate on the client can be achieved using a simple search and replace operation in the PL/SQL code to changes references to point at the alternative "CLIENT" implementations provided by WebUtil.

The final goal of WebUtil design is to add value to Oracle Forms as a product. WebUtil adds capabilities to Forms which have simply not existed before in either web or client server deployments.

The Technology Behind WebUtil

WebUtil uses the extensibility features of Oracle Forms, both in the Java client using the Pluggable Java Component (PJC) mechanism, and on the application server using the Forms interfaces to Java. Nothing in WebUtil is secret; it uses published APIs and documented techniques to provide all of its functionality. Of course one of the key benefits of the utility is that it then wraps up those complex activities inside a series of simple PL/SQL APIs.

WebUtil is designed to be extended, to add further functionality, as it is required. Much basic infrastructure, such as error diagnosis and self-installation, is provided as part of the WebUtil kernel, and customers can use these APIs to expand WebUtil with additional functionality as requirements dictate.