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Enterprise Objects Overview

The Enterprise Object technology provides a set of flexible, modular, and mature object-oriented frameworks that allow you to build data-driven applications without needing to worry about an application’s data sources. It allows you to work with objects rather than directly with the data source, which reduces development time, reduces the amount of code you need to write, and allows you to build reusable, portable business objects that can be shared between many different applications.

Enterprise Objects specializes in providing mechanisms to retrieve data from various data sources, such as relational databases via JDBC and JNDI directories, and mechanisms to commit data back to those data sources. These mechanisms are designed in a layered, abstract approach that allows you to think about data retrieval and commitment at a higher level than a specific data source or data source vendor.

In marrying relational databases to object-oriented programming, the fundamental problem is how to define the mapping between each world. To solve this problem, Enterprise Objects provides tools and frameworks for object-relational mapping to allow you to work with data objects, rather than directly with database tables. These data objects are referred to as enterprise objects.

The core element to this mapping is a model file that you build with a tool called EOModeler. This tool is documented in EOModeler User Guide, which you should read before reading this document. By understanding how to build models that Enterprise Objects can use, you'll be better equipped to understand the concepts in this book.

This chapter introduces the major concepts in Enterprise Objects. It is divided into the following sections:

• “What Does Enterprise Objects Do?” describes the core purposes of Enterprise Objects.

• “Why Enterprise Objects?” discusses the Enterprise Objects advantage.

• “What Is an Enterprise Object?” introduces the key element in Enterprise Objects applications: instances of classes that implement the EOEnterpriseObject interface.

• “Core Layers” introduces the core layers in the Enterprise Objects frameworks.

• “Key Concepts of Object-Oriented Programming” discusses some important object-oriented programming principles that you’ll encounter when using Enterprise Objects.

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