OA Framework Introduction

OA Framework Introduction

OA Framework is based on the industry-standard J2EE MVC design pattern.

The MVC architecture is a component-based design pattern with clean interfaces between the Model, View, and Controller. The Model is where the application implements its business logic. The View is where the application implements its user interface and the Controller is where the application handles user interaction and directs business flow.

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HTML request                                            HTML request

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View                    <----Controlled by ---------Controller

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OA Extension offers the following design time tools:

􀁹 UML tools to model and generate business logic.

􀁹 Guided user interface (and visual editors in a future release) to lay out client user interfaces.

􀁹 Code generation for Controller classes.

The OA Framework Model is implemented using Oracle Business Components for Java (BC4J). BC4J

provides optimized, ready-to-use implementations of the J2EE design patterns that developers otherwise

would have to code, debug, and test by hand. By leveraging BC4J's combination of tested code and

productivity tools inside the Oracle JDeveloper IDE, development teams can focus immediately and only, on

writing business logic and user interfaces instead of on designing, coding, and debugging handcrafted

application "plumbing" code.

OA Framework View is implemented using UI XML (UIX). UIX uses XML to describe the components and

hierarchy that make up an application page. UIX also provides runtime capabilities to translate that metadata

into HTML output so that it can be shown on a Browser or a mobile device. The metadata used to describe the

UI is loaded into a database repository, called Meta Data Services (MDS), at deployment time and optionally at

design time as well.

The OA Controller, which is a pure Java class implementation, handles user and application-driven

interactions. Simple page flows (such as a 2-step transaction) are implemented directly into the Controller

object; others are implemented using Oracle Workflow. In a future release, business flows will be implemented

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in a declarative manner similar to that used to define model and view objects.

Key Features

This section the following key features of OA Framework:

􀁹 Integrated development environment

􀁹 Durable personalizations and extensions

􀁹 Consistent and compelling user interface

􀁹 User interface interactivity

􀁹 Object oriented reuse

􀁹 Oracle portal interoperability

􀁹 Built-in security

􀁹 Deployment environment

Integrated Development Environment

Oracle JDeveloper with OA Extension (OA Extension) is a world-class J2EE-based integrated development

environment.

OA Extension provides features such as easy-to-use wizards, a hierarchy navigator, and a

property sheet. These features enable developers to populate the metadata for declarative application

business logic and user interfaces

Durable Personalizations and Extensions

Personalization is about declaratively tailoring the UI look-and-feel, layout or visibility of page content to suit a

business need or a user preference. Examples of personalization include:

􀁹 Tailoring the color scheme of the UI.

􀁹 Tailoring the order in which table columns are displayed.

􀁹 Tailoring a query result

Extensibility is about extending the functionality of an application beyond what can be done through

personalization. Examples of extensibility include:

􀁹 Adding new functional flows.

􀁹 Extending or overriding existing functional flows.

􀁹 Extending or overriding existing business logic.

User Interface Interactivity

OA Framework is always exploring the technology frontiers to enrich the interactivity of HTML-based user

interfaces. Along those lines, OA Framework provides several features:

Partial Page Rendering (PPR)

PPR is a means by which designated parts of a page, rather than the whole page, is refreshed when the user

performs certain actions. OA Framework supports PPR on actions such as: table record-set navigation, table

sorting, table column totaling, adding a row to a table, row-level and cell-level detail disclosure, toggling the

visibility of a Hide/Show component, populating a LOV, subtab navigation, Gantt chart refreshing and

descriptive Flexfields context switching. Moreover, developers can declaratively enable PPR events on several

components. For example, a developer can:

􀁹 Configure the selection of a poplist to cause related fields to render, be updatable, be required or be

disabled based on the selected value.

􀁹 Configure the value change of a text field to set related field values (for example, if you set a Supplier

value and tab to the next field, the dependent Supplier Site defaults automatically).

􀁹 Configure the selection of a master table's record to automatically query and display related rows in a

detail table.

Accelerator (Hot) Keys

OA Framework supports mnemonic accelerator keys for selected buttons and enables developers to assign

numeric access keys to product specific user actions.

Enhanced Save Model

OA Framework provides a default implementation to warn users when they are about to lose changes such as

when they click on a link that takes them outside the context of the current transaction. Developers can

override the default behavior on a component-by-component basis.

Smart Poplist

OA Framework supports a personalizable hybrid between a static poplist and a searchable list of values. The

poplist includes the most popular values a user uses to populate a particular attribute. The user can

personalize the values that show up in the poplist by picking new values from a list of values. Moreover, the

user can personalize the order in which values are listed in the poplist as well as remove less popular values.

This feature is also referred to as a LOV Choicelist.

LOV Auto Completion

Lists of values (LOVs) are used when the list of possible values is long and the user may want to conduct a

search before picking a value. In some business scenarios, especially with clerical jobs, the user uses a small

set of values or may find it faster to type a partial value. If the user enters a partial value in a field that is

associated with an LOV, OA Framework conducts a search before bringing up the LOV window. If the search

leads to a unique record, OA Framework completes the rest of value for the unique record and saves the user

from having to use the LOV window.

Object Oriented Reuse

OA Framework applications can be abstracted into a series of concentric layers, like an onion. The core layer

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represents the database and the surface layer represents the application pages. In between is a number of

business logic and user interface layers. This layering allows for generic code and components to be

implemented at the inner layers to maximize their reuse across the outer layers. For example, attribute

validation is implemented at the Entity Object (a BC4J object-oriented representation of a database table in the

middle tier) level. All application pages that provide the user with the ability to populate or update the value of

the subject attribute would receive attribute validation for free through the underlying entity object. On the userinterface

side, reusable components can be saved as shared regions in the metadata services (MDS)

repository and reused across several pages. An administrator can choose to personalize the shared region

such that the personalization impacts all instances of the same region across pages or personalize the shared

region only in the context of the current page.



OA Controller

Application Module

View Object

Entity Object

DB


----Data flow down stack (push)--->

<---Data Flow up stack(pull)---------

Oracle Portal Interoperability

OA Framework offers developers a simple approach to publishing OA Framework components (commonly

known as regions) as Oracle Portal-compatible portlets. Oracle Portal provides you with a common, integrated

starting point for accessing all your data. Since Oracle Portal lets you personalize the content and look of your

page, you can also personalize the application region that is displayed as a portlet. Any personalizations you

make to that portlet region appear only when you display that region from the same portlet.Built-in Security

HTML-based applications offer great user and administrator convenience, but special care must be taken to

ensure that these applications are secure. Developing HTML applications that are truly unbreakable is very

difficult, historically requiring application developers to also be security experts. In fact, most application

developers are not security experts, and they should not need to be. It is the responsibility of the application

framework to ensure that HTML transactions are authorized, private, and free from tampering. OA Framework

provides built in protection against known HTML hacking strategies, leaving the application developer free to

concentrate on application functionality. Also, since UI components are defined in metadata rather than in

code, the security protection offered by OA Framework can be advanced to keep up with the state of the art,

without requiring applications to be rewritten.

Deployment Environment

OA Framework applications are deployed using standard Oracle 10g AS / Apache and Oracle10g Database

servers. Application pages can be rendered on Internet Explorer 5.0 or above, Netscape 4.73 or above and

Mozilla 1.5 or above. The data and middle tiers can be deployed on several platforms including Linux, UNIX

and Windows.

Summary
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Based on the Model-View-Controller (MVC) architecture, OA Framework lets application developers focus on

the business requirements rather than on the underlying technologies. By using declarative and guided-coding

(and soon visual) techniques, OA Framework allows application developers who are not necessarily J2EE

experts to quickly become productive. OA Framework-based applications offer a highly consistent user

experience with the highest levels of user interactivity without a client footprint. Applications are optimized for

sub-second response to most user interactions and competitive scalability trends. OA Framework exploits its

declarative and object-oriented architecture to offer the most durable personalization and extensibility

capabilities on the market, at a fraction of the cost. OA Framework features translate to lower costs of

ownership, better user experience and competitive deployments.