Simplified structure
The J2EE platform supports simplified, component development model, because J2EE is based on the Java programming language and J2SE platform, which provides a written, running, all servers that follow J2EE standards support the model.
The EJB component makes it easier to write applications. Although the EJB architecture is complex, application developers generally write code access to the system service, and EJB containers implement system-level services, such as transactions, security, etc.
In addition, J2EE also supports heterogeneous environments. Based on J2EE-based applications do not rely on any particular operating system, middleware or hardware, the design-based J2EE-based program can be deployed to a variety of platforms, which can be deployed to various platforms, which is very heterogeneous. Pivotal. The J2EE standard also allows customers to order off-the-heeled components with J2EE-compatible third-party, deploy them into the heterogeneous environment, saving the costs required to develop the entire program.
2. Improve development efficiency
Due to the use of component technology, the application development can be divided according to the development of the developer, and the overall development efficiency is provided in parallel. For example: Graphic designer creates a JSP template, the business logic is completed by experts in this field, JSP pages and EJBs are completed by Java engineers, and the application's assembly and deployment are completed by other members of the team, many of them can be performed at the same time, help Development of the acceleration application.
3. Strong portability
In addition to the inherent portability of Java language, the EJB architecture provides a standardized application programming interface between Bean and the container that supports this bean, which enables developers to transplant Beans from one operating environment to another. Operating environment without rewriting its source code.
4. Good reuse
Since each software component is strictly separated from the EJB model, the server-side application can be installed from the existing software components, which is the same as the existing JavaBean can be equipped with client applications. Reuse.
5. Easy to maintain
Component-based design simplifies the maintenance of applications. Since components can be independently updated and replaced, new features can be easily increased by updating specific components in the application.
6. Scalability
Companies must choose a server-side platform to meet those new customers who have commercial actions on them. Applications based on J2EE platforms can be deployed to various operating systems, for example, can be deployed to high-end UNIX or other large machine systems. Suppliers in J2EE are more widely load balancing strategies to eliminate bottlenecks in the system, allow multiple servers to integrate deployment, achieving highly scalable systems to meet future business applications.
7. Widely accepted
The main IT suppliers adopt an EJB architecture. Different suppliers' products are all interoperable as long as they meet the EJB architecture.
8. Protection investment
Since companies must adapt to new business needs, make full use of existing corporate information system investments, rather than re-establishing, the full update plan is especially important, so that one is gradually (rather than radical, all-in-counter) The server platform built on existing systems is desirable to be most companies.
The J2EE architecture can make full use of users' investment, by allowing existing information systems and asset "package" in the J2EE application, and does not require customers to replace the existing technology. In fact, companies that store data in the relational database have already had a prototype entry bean, waiting for access to the EJB shell.
