GlassFish is a robust and scalable Java application server that provides support for various Java enterprise technologies. One such technology is Enterprise JavaBeans (EJB), which is a server-side component architecture for building distributed systems in Java.

EJBs are reusable and portable components that encapsulate business logic and can be deployed on any EJB container, such as GlassFish. They provide a wide range of functionalities, including transaction management, concurrency control, security, and messaging.

GlassFish offers a comprehensive implementation of EJB that simplifies the development and deployment of distributed applications. With GlassFish, developers can easily create and manage EJBs using annotations and XML deployment descriptors.

To get started with EJBs in GlassFish, follow these steps:

Step 1: Define the EJB

Create a new Java class that represents the EJB and annotate it with @Stateless, @Stateful, or @Singleton to define the type of EJB you want to create. For example:

@Stateless
public class MyEjb {
    // Business logic and methods
}

Step 2: Deploy the EJB

To deploy the EJB, you need to package it into an Enterprise Archive (EAR) or a Web Archive (WAR) file. GlassFish supports both packaging formats. Once you have packaged your EJB, deploy it to GlassFish using the administration console or the command-line interface.

Step 3: Access the EJB

To access the EJB from a client application, you can use dependency injection or the JNDI API. GlassFish supports both approaches. Here’s an example of accessing an EJB using dependency injection:

@ManagedBean
public class MyManagedBean {
    @EJB
    private MyEjb myEjb;

    // Access and use the EJB methods
}

Conclusion

GlassFish provides robust support for Enterprise JavaBeans (EJB) technology, making it easy to develop and deploy distributed applications. By leveraging the power of EJBs in GlassFish, developers can build scalable and secure enterprise systems with ease.

#Java #GlassFish #EJB