Skip to main content

Overview of EJB and Lifecycle





The container is responsible for loading, activating, and in general maintaining the "life-cycle" of objects it provides. EJB have a fairly complex life-cycle. There are several kinds of EJB:
Session Beans: These may be either stateful or stateless, and are primarily used to encapsulate business logic, carry out tasks on behalf of a client, and act as controllers or managers for other beans.
 

Entity Beans: Entity beans represent persistent objects or business concepts that exist outside a specific application's lifetime. They are typically stored in a relational database. Entity beans can be developed using bean-managed persistence, which is implemented by the developer, or container-managed persistence, implemented by the container.

 
Message-Driven Beans: Message-driven beans listen asynchronously for Java Message Service (JMS) messages from any client or component and are used for loosely coupled, typically batch processing.
Labels:

Popular posts from this blog

Design Patterns (TID)

The pattern is an organised way of solving some specific class of problems. These patterns come in to the picture at analysis and high-level-design phase. The first step of applying one pattern to the code base is first to understand the find the vector of change in the code base. Next step is to isolate the things that are subject to change form the things that are not. That is adding a layer of abstraction to the code. The goal of design patterns is isolating the changes in your code. Understand Inheritance and Composition as a solution to a specific class of problems. Inheritance : - It allows you to express differences in behavior (that's the thing that changes) in objects that all have the same interface (that's what stays the same). Composition : - Composition can also be considered a pattern, since it allows you to change—dynamically or statically—the objects that implement your class, and thus the way that class works. Some principles of designing the c...
Read more

Adobe Firefly

Adobe Firefly is designed to help developers create custom applications more quickly and easily. The platform is built on top of Adobe's existing Experience Cloud, which provides a range of tools for managing customer data and creating personalized experiences. One of the key features of Adobe Firefly is its ability to integrate with a wide range of other technologies and services. This means that developers can use the platform to build applications that connect with everything from social media platforms to IoT devices. Another important aspect of Adobe Firefly is its focus on speed and efficiency. The platform includes a range of pre-built components and templates that developers can use to quickly create new applications. It also includes a range of tools for testing and debugging applications, which can help to speed up the development process. Overall, Adobe Firefly looks like an exciting new platform for developers who are looking to create custom applications quickly and ef...
Read more

Primitive Obsession with Example

Primitive Obsession is the name of a code smell that occurs when we use primitive data types to represent domain ideas. For example, we use a string to represent a message or an integer to represent an amount of money. For Example: Code with Primitive Obsession // primitiveObsession.java public class primitiveObsession { public static void main ( String args []) { Integer [] cityPopulations = { 13000000 , // London 21903623 , // New York 12570000 , // Tokyo 1932763 , // Stockholm 1605602 , // Barcelona 4119190 // Sydney }; for ( Integer cityPopulation : cityPopulations ) { System . out . println ( cityPopulation ); } } } public class City { private final String name ; private final int population ; private final Continent continent ; public String getName () { return name ; } public int getPopulation () { return population ; } public Continent ge...
Read more