What are an Enterprise Beans?

[SKREECH]

I have just started with the J2EE components. I know that the Enterprise JavaBeans (EJB) are implemented by the J2EE components. But I want more information about an Enterprise Beans. Can anyone explain me what are an Enterprise Beans.?? Also I don't know why exactly we use enterprise beans. Is there any benefits using an enterprise beans..?? Also please explain me exactly when we use an enterprise beans.?? Hoping that someone can help me quickly..!!

[void]

Before you proceed to the coding, you should always understand the concepts of that particular thing. So before knowing when to use the beans, I think that you should know about the beans. Enterprise JavaBeans (EJB) can be said as server-side component architecture which are used for the modular construction of enterprise applications. Also the beans are said as server-side model that encapsulates the business logic of an application. Hope that you would have understand what does the beans exactly means.!!

[Allan.d]

For creating the Java applications by combining with the other resources can be done using an enterprise bean. There are three types of an enterprise beans which are as follows :

1. Entity beans.
2. Session beans.
3. Message-driven beans.

All beans that are mentioned above resides in Enterprise JavaBeans containers. An interface between the beans and the application server is provided by the EJB container. An earlier versions of beans require connections to a form of persistent storage to store permanent data.

[MindSpace]

An enterprise beans are used because of their features which are the benefits for the programmer of Java. Only because of their features an enterprise beans are being used very widely for developing large and distributed applications. The system-level services which includes the security authorization and the transaction management are provided by the EJB container to the enterprise beans. Because of this facility the developer can concentrate on solving the problem occurred in it which proves to be very helpful. Also the client developer does not bother about the code that implements business logic or the logic to access the databases.

[absolute55]

You want to know that when the Enterprise Beans are being used.!! The following are couple of examples in which you will come to know that exactly when to use an Enterprise Beans. Just have a look on the following scenarios :

1. The applications that are developed by using an enterprise beans can be examined and dealt with a variety of clients. Such beans are having very few lines of the codes so that the client can locate the enterprise beans. So using an Enterprise Beans over here causes the benefit.
2. The transaction are also supported by an enterprise beans to make sure the integrity of the database. Transaction is the mechanism of managing the concurrent access of shared objects.

[Katty]

You should have known much about the Enterprise Beans. So, according to me, you should also know about the contents of an Enterprise Bean, I have provided you with the useful information about the same. You must provide the following files to develop an enterprise bean :

• Enterprise bean class : This class is used for implementing the methods defined in the interfaces.
• Deployment descriptor : This is the file in which the information about the bean such as its persistence type and transaction attributes are involved. Such files can be an XML file providing the mentioned information.
• Interfaces : This file is used when the remote and home interfaces are required for remote access.
• Helper classes : Other classes needed by the enterprise bean class, such as exception and utility classes.