What is the difference between JavaBean and EJB

You may be using JavaBean now, but you don't know it yet. If you have a Java-enabled browser, there is no limit to using JavaBean on your desktop. You can use a Web page to make a bean part of a small application.

You will soon interact with the JavaBean as a visual part of the browser, and then those JavaBean will be with the EJB interface on the server. This capability can also be extended to the Internet and intranet.

JavaBean and Server beans (often called Enterprise JavaBean (EJB)) have some basic similarities. They are objects or components that are created with a set of attributes to perform their specific tasks. They also have the ability to obtain additional features from the containers currently residing on the server. This makes the behavior of the bean different depending on the specific task and the environment in which it is located.

This opens up huge business opportunities. Because JavaBean is platform-independent, for future solutions, vendors can easily roll out their client-side JavaBean to different users without having to create or maintain different versions.

These JavaBean can be used in conjunction with EJBS that perform commercial functions such as ordering, credit card processing, electronic remittance, inventory allocation, transportation, and so on. There is tremendous potential, and that is the potential that the component agent (Websphereapplication Server Enterprise) design offers.

JavaBean is a component that has interfaces or attributes associated with it internally so that beans developed by different people at different times can be queried and integrated. You can build a bean and bind it to other beans at a later time when it is constructed.

This process provides a way to build and then reuse, which is the concept of the component. You can deploy such a single application as a stand-alone program, an ActiveX component, or in a browser.

JavaBean is different from a pure object because of its external interface (that is, the property interface). This interface allows the tool to read the function to be performed by the component, hook it up with other beans, and insert it into other environments.

JavaBean are designed to be local to a single process and are usually visible at run time. This visual component may be a button, list box, graphic, or chart-but this is not required.

Executable Components

A server Bean or EJB is an executable component or business object that is deployed on a server. There is a protocol that allows remote access to or install or deploy them on a specific server. There are a number of mechanisms that allow them to authorize the main aspects of service security, transactional behavior, concurrency (ability to be accessed concurrently by multiple clients), and persistence (how long the state can be saved) to the container on the EJB server where it resides.

When installed in a container, they get their own behavior, which provides different quality services, so it is critical to choose the right EJB server. This is the advantage of the IBM WebSphere Enterprise Edition.

An EJB is a non-visual remote object that is designed to run on a server and invoked by a client. EJB can be built through multiple non-visual JavaBean. They have a deployment descriptor that is the same as the JavaBean property: It is a description of the bean that can later be read by the tool. EJBs are also platform-independent and, once written, can be used on any Java-enabled platform, including clients and servers.

Because the EJB is generated by a toolset such as IBM VisualAge for Java, it is a server-based object and is used for remote invocation. They are installed on the EJB server and get a remote interface to invoke as they would call other CORBA remote objects.

ActiveX Objects

JavaBean can be deployed as an ActiveX object, although the EJB proxy can do so, but because ActiveX runs on the desktop, the EJB itself cannot be an ActiveX object. To do this on a platform-dependent, Windows-only platform, developers can transform JavaBean into ActiveX components.

Benefits

The main benefit of EJBS is that when building a bean, the bean developer can specify what type of behavior is required, without having to prescribe how to do it. Development is divided into two parts: the programmer develops the bean and then verifies that it works with the build tool and includes a deployment descriptor that identifies the type of service quality behavior that is required.

Next, another programmer can take the bean, use the deployment tool that reads the EJB deployment descriptor, and then install the bean into a container on Enterprise Java Server.

In the second step, the deployment tool takes some action-this could mean generating code such as state-saving code, placing a transaction hook, or performing a security check. All of these operations are generated by the deployment tools, and bean developers and deployment personnel can be different people.

You can use deployment tools to rewrite any platform-independent JavaBean into a reliable quality of service, platform-specific EJB to meet the specific needs of existing business systems and applications. This is why EJB servers are so important to integrated systems, networks, and architectures.

EJB and IBM WebSphere Enterprise Edition

When used in IBM WebSphere Enterprise Edition, EJB can be configured as a managed business object. The container that accepts the services they authorize is the container to which they are installed. Maps the persistence portion of an EJB to a data or state object.

EJB servers provide a different quality of service for EJBS, and choosing the right EJB server may be critical to satisfying a complete business requirement. The component Agent feature is extremely robust and provides advanced functionality such as load balancing and multiple machines in a server group.

It also has much more system management capabilities than is advocated by the Enterprise Java Server (EJS) specification. As a result, JavaBean or EJBS written according to basic standards can run on the WebSphere Enterprise Edition that uses the component Agent feature and get all of the additional functionality.

The EJB server also provides unique features and quality of service, and is not exactly the same. The IBM component agent has some powerful features-for example, scalability, which allows developers to deploy EJBS to different types of servers from small systems to large networks. Developers can start small, for example, in one department, first deployed on a LAN's Java server and, once ready, know that JavaBean and EJBs created there can be deployed to the global network.

The developers can then test and familiarize themselves with the beans, test runs, make samples, and so on. When satisfied, developers can dramatically scale up by moving it to a high-performance server. JavaBean and EJBs are not limited by any computer architecture boundaries.

They are written in Java and can be run on any system that has a Java virtual machine and can deploy objects using any Enterprise java Server (EJS). As a result, developers can now build on a convenient system and later deploy on a convenient system without having to be the same machine or the same type.

IBM WebSphere Enterprise Edition supports the deployment of business objects to multiple servers. EJB is integrated into the component broker function as a business object and processed as any other business object. As a result, EJBS can connect to the selected backend system and perform any required operations to meet their business needs.

This becomes the infrastructure that the component agent provides for EJBS. By using the component agent as an EJB server, developers will be able to continue to use the current legacy system and provide it with an e-business interface.

To enable the EJB to work in the WebSphere Component Agent environment, you can use the Component Agent Deployment tool to install it on one or more servers and then add it to a named server so that it can be found globally.

Anyone who can access a public naming server can find it, find its host, and execute methods on the host, creating EJBS as well. This is what the agent component is going to do.

Concluding remarks

The full significance of a Bean is not only its existing capabilities, but also its competitive potential for business. It architects and application developers can now focus exclusively on business logic, leaving the underlying work, such as transaction, persistence, and security, to the server. The component Agent feature of WebSphere will provide all these (and backend access) and object transaction managers.