Добавил:
Опубликованный материал нарушает ваши авторские права? Сообщите нам.
Вуз: Предмет: Файл:
Enterprise JavaBeans™ Specification, Version 2.0 - Sun Microsystems.pdf
Скачиваний:
14
Добавлен:
24.05.2014
Размер:
2.71 Mб
Скачать

Sun Microsystems Inc

Overall goals

Enterprise JavaBeans 2.0, Public Draft

Goals

Chapter 2 Goals

2.1 Overall goals

The Enterprise JavaBeans (EJB) architecture has the following goals:

The Enterprise JavaBeans architecture will be the standard component architecture for building distributed object-oriented business applications in the Java™ programming language. The Enterprise JavaBeans architecture will make it possible to build distributed applications by combining components developed using tools from different vendors.

The Enterprise JavaBeans architecture will make it easy to write applications: Application developers will not have to understand low-level transaction and state management details, multi-threading, connection pooling, and other complex low-level APIs.

Enterprise JavaBeans applications will follow the Write Once, Run Anywhere™” philosophy of the Java programming language. An enterprise Bean can be developed once, and then deployed on multiple platforms without recompilation or source code modification.

The Enterprise JavaBeans architecture will address the development, deployment, and runtime aspects of an enterprise application’s life cycle.

27

5/31/00

Sun Microsystems Inc.

Goals

Enterprise JavaBeans 2.0, Public Draft

EJB Releases 1.0 and 1.1

The Enterprise JavaBeans architecture will define the contracts that enable tools from multiple vendors to develop and deploy components that can interoperate at runtime.

The Enterprise JavaBeans architecture will be compatible with existing server platforms. Vendors will be able to extend their existing products to support Enterprise JavaBeans.

The Enterprise JavaBeans architecture will be compatible with other Java programming language APIs.

The Enterprise JavaBeans architecture will provide interoperability between enterprise Beans and Java 2 Platform Enterprise Edition (J2EE) components as well as non-Java programming language applications.

The Enterprise JavaBeans architecture will be compatible with the CORBA protocols.

2.2EJB Releases 1.0 and 1.1

Enterprise JavaBeans Release 1.0 focused on the following aspects:

Defined the distinct “EJB Roles” that are assumed by the component architecture.

Defined the client view of enterprise Beans.

Defined the enterprise Bean developer’s view.

Defined the responsibilities of an EJB Container provider and server provider; together these make up a system that supports the deployment and execution of enterprise Beans.

Defined the format of the ejb-jar file, EJB’s unit of deployment.

Release 1.1 augmented this with a focus on the following:

Provided better support for application assembly and deployment.

Specified in greater detail the responsibilities of the individual EJB roles.

2.3Goals for Release 2.0

Enterprise JavaBeans Release 2.0 focuses on the following aspects:

Define the integration of EJB with the Java Message Service.

Provide improved support for the persistence of entity beans.

Provide improved support for the management of relationships among enterprise beans.

5/31/00

28

Sun Microsystems Inc

Goals for Release 2.0

Enterprise JavaBeans 2.0, Public Draft

Goals

Provide a query syntax for entity bean finder methods.

Provide support for additional methods in the home interface.

Provide for network interoperability among EJB servers.

29

5/31/00

Sun Microsystems Inc.

Goals

Enterprise JavaBeans 2.0, Public Draft

Goals for Release 2.0

5/31/00

30