1. Understanding Oracle WebLogic Server
  2. Developing Applications in WebLogic Server

6 Developing Applications in WebLogic Server

WebLogic Server implements Jakarta Platform, Enterprise Edition (Jakarta EE) Version 8.0 technologies. Jakarta EE is the standard platform for developing multitier enterprise applications based on the Java programming language.

This chapter includes the following topics:

WebLogic Server and the Jakarta EE Platform

With Jakarta EE, development of Jakarta enterprise applications has never been easier or faster. The aim of the Jakarta EE platform is to provide developers with a powerful set of APIs while shortening development time, reducing application complexity, and improving application performance. The technologies that make up Jakarta EE were developed collaboratively by several software vendors. For background information on Jakarta EE application development, refer to the Java EE Tutorial at: https://javaee.github.io/tutorial/toc.html.

An important aspect of the Jakarta EE programming model is the introduction of metadata annotations. Annotations simplify the application development process by allowing a developer to specify within the Java class itself how the application component behaves in the container, requests for dependency injection, and so on. Annotations are an alternative to deployment descriptors that were required by older versions of enterprise applications (Java EE 1.4 and earlier).

Starting in Java EE 5 and continuing in Jakarta EE 8, the focus has been ease of development. There is less code to write – much of the boilerplate code has been removed, defaults are used whenever possible, and annotations are used extensively to reduce the need for deployment descriptors.

  • EJB 3.2 provides simplified programming and packaging model changes. The mandatory use of Java interfaces from previous versions has been removed, allowing plain old Java objects to be annotated and used as EJB components. The simplification is further enhanced through the ability to place EJB modules directly inside web applications, removing the need to produce archives to store the web and EJB components and combine them together in an EAR file.

  • Jakarta EE 8 continues the focus on modern web applications of Java EE 7 and broadening the range of such applications. The key goals of the Jakarta EE 8 platform are to modernize the infrastructure for enterprise Java for the cloud and microservices environments, emphasize HTML5 and HTTP/2 support, and enhance the ease of development through new Contexts and Dependency Injection (CDI) features, and further enhance the security and reliability of the platform.

  • Constructing web applications is made easier with JavaServer Faces (JSF) technology and the JSP Standard Tag Library (JSTL). Jakarta EE 8 supports rich thin-client technologies such as AJAX, for building applications for Web 2.0.

WebLogic Server Jakarta EE applications are based on standardized, modular components. WebLogic Server provides a complete set of services for those modules and handles many details of application behavior automatically, without requiring programming. Jakarta EE defines module behaviors and packaging in a generic, portable way, postponing runtime configuration until the module is actually deployed on an application server.

Jakarta EE includes deployment specifications for web applications, EJB modules, web services, enterprise applications, client applications, and connectors. Jakarta EE does not specify how an application is deployed on the target server—only how a standard module or application is packaged. For each module type, the specifications define the files required and their location in the directory structure.

Jakarta EE is platform independent, so you can edit and compile code on any platform, and test your applications on development WebLogic Servers running on other platforms. For example, it is common to develop WebLogic Server applications on a PC running Windows or Linux, regardless of the platform where the application is ultimately deployed.

For more information, refer to the Jakarta EE specification at: https://jakarta.ee/specifications/platform/8/.

Parent topic: Developing Applications in WebLogic Server

Overview of Jakarta EE Applications and Modules

At runtime, a Jakarta EE application is a type of module. A WebLogic Server Jakarta EE application consists of one of the following modules or applications running on WebLogic Server:

  • Web application modules—HTML pages, servlets, JavaServer Pages, and related files. See Web Application Modules in Developing Applications for Oracle WebLogic Server.

  • Jakarta Enterprise Beans (EJB) modules—entity beans, session beans, and message-driven beans. See Enterprise JavaBean Modules in Developing Applications for Oracle WebLogic Server.

  • Connector modules—resource adapters. See Connector Modules in Developing Applications for Oracle WebLogic Server.

  • Enterprise applications—web application modules, EJB modules, resource adapters and web services packaged into an application. See Enterprise Applications in Developing Applications for Oracle WebLogic Server.

  • Web services—See WebLogic Web Services in Developing Applications for Oracle WebLogic Server.

A WebLogic application can also include the following WebLogic-specific modules:

Parent topic: Developing Applications in WebLogic Server

Roadmap for Developing Applications in WebLogic Server

The WebLogic Server documentation set includes several introductory, procedural, and reference topics, including examples, that help you understand how to develop Jakarta EE applications on WebLogic Server.

Table 6-1 Roadmap for Developing Applications in WebLogic Server

Major Task Subtasks and Additional Information

Learning more about application development

Setting up your development environment

Designing your application

Building your application

Using development tools

Moving your application to a production environment

Application examples

Jakarta EE API programming guides

Javadoc and API reference

General reference

Parent topic: Developing Applications in WebLogic Server