Use of EJB design in enterprise applications

[GracieSingh]

Hi all,

EJB 3.0 is based on Plain Old Java Objects services to end business services and Database Persistence of the component model. Most of the applications will include the EJB business logic components and applications for the Web front-end display JSF components. I want to know the use of EJB design in enterprise applications. Thanks and advance.

[Reegan]

Most of the applications will include the EJB business logic components and applications for the Web front-end display JSF components. On the surface, EJB and JSF complement each other, but they are designed in accordance with their concept of an independent framework, which both can not alone solve all computational problems. For example, EJB3 using annotation (annotation) to configure the services, while the use of the JSF XML. EJB3 and JSF component level, the framework is not sensitive to each other, it is best used in combination. But the Java EE 5 specification does not provide how to integrate the two component model of the standard method. To integrate EJB3 and JSF, developers must manually operational components and Web Components banded together to enable cross-frame call a method. Check and reply.

[opaper]

You can put new name is simple to EAR Application Project, this project includes three projects, namely JPA Project, EJB Project, Web Project, the following steps will introduce these three projects. Target Run time to JBoss v4.2, EAR version is 5.0, Configuration for Default Configuration for JBoss v4.2. Click Next select Generate Deployment Descriptor, click Finish. New name for simple JPA the JPA project, Configuration for Default Configuration for JBoss v4.2, select the Add project. Check and reply.

[Praetor]

I give you to the sample introduction section of the UML Class diagram in EJB. Add id-based key, in the EJB3.0, each entity Bean must have a primary key, primary key can be a basic type, can also be a class. Both as a primary key Entity Bean in memory the identifier, but also as a data table row identifier. It is the entity Bean is indispensable and must be unique. Table named product. Entity Bean property of the respective members of the table is mapped to the corresponding field of product. Modify the primary key is generated for the increment, to the primary key, add the following code: @ GeneratedValue (strategy = GenerationType.AUTO). Check and reply.

[Katty]

The specification includes Bean provider, application assembler, EJB container, EJB configuration tool, EJB service provider, system administrator. This is inside, EJB containers EJB was able to run the core. EJB container manages the EJB creation, revocation, activation, deactivation, and DatabaseConnections, and so important core work.JSP,Servlet, EJB, JNDI,JDBC, JMS. Component is the EJB container EJB proxy, EJB components are created and managed by the container. Customers to access real EJB container components. Best of luck.

[kelfro]

EJB including Session Bean, Entity Bean, Message Driven Bean, based on JNDI, RMI, JAT and other technology. Session Bean in J2EE Applications are used to complete some Servers Side of the business operations, such as access to the database, call other EJB components. Entity Bean be used to represent the application systems used in the data. For the client, Session Bean is a non-persistent object, which implements some running on the server business logic. Best of luck.