FAQs in ADF: Basic Architecture

What is Oracle Fusion Middleware?

Oracle Fusion Middleware is a standards-based family of products that are often deployed and used in conjunction with one another to develop Java EE applications, providing the benefits of common security, management, deployment architecture, and development tools.

What are the technologies of Oracle Fusion Middleware?

• Oracle BPEL Process Manager
• Oracle Web Services Manager
• Oracle Business Rules Engine
• Oracle Enterprise Service Bus
• Oracle Business Activity Monitoring
• Oracle Services Registry
• Oracle JDeveloper

What is Oracle Application Development Framework?

Oracle ADF is an end-to-end application framework which is built on Java EE standards and open-source technologies to simplify and accelerate implementing Java EE applications. It is fully extensible and customizable by adding or modifying libraries. Oracle ADF simplifies Java EE development by minimizing the need to write code that implements design patterns and the application infrastructure.

What is Model-View-Controller?

It is a popular design pattern used by ADF. Design patterns are simply a convenient way of reusing object-oriented concepts between applications and developers. The main idea behind design patterns is to document and catalog common behavior patterns between objects so that developers can then make use of these patterns rather than re-create them.

• The model manages the data of the application domain, responds to requests for information about its state (usually from the view), and responds to instructions to change state (usually from the controller).
• The view manages the presentation of the application output (UI) to the user.
• The controller interprets the mouse and keyboard inputs from the user, commanding the model and/or the view to change as requested.

What is JDeveloper?

Oracle JDeveloper is a comprehensive development tool that provides facilities to build Web applications using a common development tool set. This tool has evolved to provide an integrated environment that enables a developer to design, develop, troubleshoot, optimize, and deploy Java EE applications. JDeveloper is the integrated development environment (IDE) that utilizes the Application Development Framework. There are many other IDEs too available for Java EE Application developments.

Why JDeveloper?

• Oracle JDeveloper is an integrated development environment (IDE) for building service-oriented applications by using the latest industry standards for Java, XML, Web services, and SQL.

• It supports the complete development life cycle with features for modeling, coding, debugging, testing, profiling, tuning, and deploying applications.

• It embraces popular open source frameworks and tools, providing built-in features for Struts, Ant, JUnit, XDoclets, and CVS, so that you can use these open source tools to streamline the development process.

• JDeveloper is a 100% Java-based tool. Because of this, it is a cross-platform IDE that runs on Windows, Linux, Mac, and various Unix-based systems.

• JDeveloper can access any JDBC-compliant database.

• Applications built with JDeveloper can be deployed to any Java EE–compliant application server.

What are the main features of JDeveloper?

JDeveloper features that facilitate ease of application development include:

• Application Navigator
• Database Navigator
• Editor (code or visual editors)
• Component Palette
• Resource Palette (IDE and Application)
• Data Controls panel
• Structure Window
• Property Inspector
• Log Window

What is ADF BC?

Oracle ADF Business Components (ADF BC) provides building blocks that help you to create the business services part of your application. That is, it governs interaction between the rest of the application and the data stored in the data source, providing validation, specific services, and other business logic.

• ADF Business Components are implemented in metadata that you write by using wizards and that you edit declaratively.
• It is based on standard Java and XML.
• It implements all the popular Java EE design patterns, such as Model/View/Controller, Interface/Implementation Separation, and Session Façade.
• It organizes components into packages.
• Most of the classes and interfaces comprising the ADF BC prebuilt codes are in the oracle.jbo or the oracle.jbo.server packages.

What are the types of ADF BC?

• Entity objects: represent objects in the data source (usually tables, views, and synonyms in a database).
• Associations: represent relationships between Entity objects (such as foreign key relationships).
• View objects: collect data from the data source, usually by a SQL query.
• View links: represent relationships (such as master-detail relationships) between view object result sets.
• Application modules: provide a single point of access to the view objects and view links.

What is ADF BC Tester?

JDeveloper provides a way to test the data model without creating a client application. You can perform this testing by using the Business Component Browser, sometimes also referred to as the Business Component Tester or the BC Tester.
To use the Business Component Browser to test the data model, you right-click the application module in the Application Navigator and select Run from the context menu.

What is ADF Data Controls?

ADF Model implements the JSR-227 service abstraction called the data control which provides data control implementations for the most common business service technologies—EJB, Web services, TopLink, Java classes, and ADF Business Components. Whichever implementation you choose, JDeveloper and ADF work together to provide you a declarative, drag-and-drop data binding experience as you build the user interface for your application.
When you create an ADF BC application module, it is automatically exposed as a data control, including all the view object and view link instances that it contains.

What are the types of View Objects?

• Updatable View through Entity Objects: Using entity object references enables view object instances to update data, use validation and other business rules from the entity object definition, and immediately synchronize data with other view object instances.
• Read-only Access View: SQL-only view objects bypass entity cache population and are faster for many applications. Note that view objects of this type save changes in memory only, and are not persisted in the database.

What will happen if I change the database table or view on which my Entity Object is based?

If you alter a table or view for which you have already created an entity object, the existing entity is not disturbed by the presence of additional attributes in its underlying table. However, if you want to access the new table column in your application, you first need to synchronize the entity object with the database table. To perform this synchronization from JDeveloper, right-click the entity object in question and choose Synchronize with Database from the context menu.