Home > Articles > Certification > Other IT

  • Print
  • + Share This
This chapter is from the book


In this section, we examine the best uses for each of the various components of the JEE web technology stack. Almost all the components can be used to tackle any presentation/flow control/business logic problem, but the specifics of JSPs, Servlets, JSF, and so on mean that they each are better-suited to specific scenarios, as detailed here.

JSPs and Servlets—Standard Uses

JSPs handle the presentation of data to the end user. They should contain no business logic. A good rule of thumb is to minimize or eliminate entirely all Java code from JSPs and replace it instead with either EL, the JSTL, or a custom/third-party tag. This guideline tends to reinforce the role of JSPs as the V in MVC—that is, the View.

JSF—Standard Uses

The standard uses for JSF are the same as for JSP. As an architect, you are faced with a choice: either continue to use JSP with JSTL and a good MVC framework, or use JSF. They do the same thing. Also, they are not mutually exclusive. It is perfectly possible to add tags to a JSP page that represent a specific JSF UI component, resulting in a hybrid solution. JSF garnered a significant amount of bad press when it first launched (as have many 1.0 implementations of specifications in the JEE platform), but it has matured since then. Many architects, however, simply see no need for it and prefer JSP with JSTL and EL.

Web-Centric Implementations

As intimated earlier, a significant proportion (exact figures are not available and indeed vary by industry vertical) of all JEE applications in existence today are deployed using only a web container—that is, they do not use EJBs. This class of JEE application is termed web-centric.

The current version of the exam tests this concept in detail. As a JEE architect, you are perfectly entitled to stipulate that EJBs not be used in your design, but you must clearly understand why that decision is mandated and the impact of that decision on your developers as they implement the business logic. The exam tests this concept by presenting you with a set of scenarios. Scenarios that have a strong messaging, transaction, or security management component are all candidates where an EJB-centric implementation is warranted and indeed necessary. (Let's be blunt—choosing EJB is the right answer.) Scenarios where ease of development is key, where an existing application is already web-centric, or where transactions are not key to the business (read-only or read-mostly) mean that you should choose a web-centric answer from those provided in the exam.

There are some stand-out reasons where using EJB is simply not warranted. The most straight-forward example is a standard Create, Read, Update, and Delete (CRUD) application built using Struts to organize and control the presentation and business logic tiers, and Hibernate plus a DAO access layer to implement the persistence tier. Assuming that there are no asynchronous messaging requirements or JMS queues or topics to access, and that the functionality contained in the web container for concurrency control, security, and session management is sufficient, then the right decision is to adopt a web-centric approach.

Now, let's consider an alternative scenario. You work for XYZ Bank, a large multinational bank with investment and retail operations, which has invested significant amounts of capital into a transactional system based on mainframe technology over the last thirty years. Ensuring system reliability and security are paramount; there is absolutely no room for data corruption from edge conditions, such as the lost update or optimistic locking going wrong. If the system enters into an unknown state because of a technology failure, not only will the system need to be brought back within 10 minutes in order to avoid a service-level agreement (SLA) breach, the relevant regulatory authorities must also be notified and a full system audit will be enforced. As the solution architect, do you believe that using only the web container segment of the JEE platform is sufficient to meet the non-functional requirements detailed here?

We would answer this rhetorical question as follows: It is possible to fulfill the preceding scenario using only a web framework, but we would not be comfortable in doing so. Many aspects of the EJB framework lend themselves very well to this type of deployment; choosing to use only a web framework will essentially force you, as the architect, into replicating in your code the reliability and availability characteristics that already exist in the core JEE platform. This is not a good use of your time and will result in a buggier implementation that needs to be maintained moving forward.

EJB-Centric Implementations

Let's reconsider the bank scenario laid out in the previous section. Looking at the business requirements, we can see that they translate into non-functional requirements (NFRs) focusing on system correctness, reliability, and security. In this scenario, and answering the question posed in the last section, assuming that the internal bank systems can be accessed by a non-EJB solution, it is possible to achieve a solution that will meet the NFRs using only a web-centric solution. But, and this is the key point, you will need to commit your team to writing entire modules of custom code to replace features that you get from an EJB container for free. In addition, it is likely that you will also need to take advantage of vendor-specific libraries/mechanisms to implement these modules. That is the key point. In the scenarios examined here, there is no right or wrong answer—just more correct and less correct. And that is the key role of an architect: to examine the possible solutions and select the most correct solution, taking into account the vagaries of the known set of business requirements.

Rationale for Choosing Between EJB-Centric and Web-Centric Implementations

As you may have gathered from the two preceding sections, neither we, nor indeed the exam, believe that a web-centric or an EJB-centric architecture is always right or always wrong. The decision to select one over the other is based purely on an impassionate review of the facts relating to a specific project. In order of decreasing importance, the pertinent facets to consider are as follows:

  • Transaction requirements—The more onerous, the bigger the reason to select EJB.
  • Security requirements—Again, the more onerous, the bigger the reason to select EJB.
  • Messaging requirements—Need to integrate with an asynchronous messaging system—Again, if present, a clear reason to select message-driven beans (MDBs); that is, the EJB-centric approach.
  • Performance.
  • Ease of development.
  • Scalability.
  • Existing team skills or existing project implementation.

The last four facets listed are not reasons in themselves that will conclusively force you to choose one approach over the other; indeed, the waters have been muddied in recent JEE releases for each. The primary focus for EJB 3.0 (and continued in 3.1) is improving the ease of development. As you will see in Chapter 4, the general consensus is that EJBs are now, at last, easy enough to develop that their use is warranted in situations where previously system designers did not specify their use. Assuming an efficient container implementation, stateless session beans should be as efficient as Servlets/Action handlers in executing business logic on the server side as a proxy for the client. The obvious exception here is stateful session beans. The need to maintain one session bean per connected client for the duration of the conversation will always make stateful session beans a poor scaling design choice, suitable only for a small subset of applications with very specific requirements.

The Future of Client-Server Communication

It is worth noting that the current release of the exam was written in 2007 and contains material on Asynchronous JavaScript and XML, or AJAX. Architects must understand the benefits of AJAX as they relate to providing an enhanced end-user experience and how the JEE 5 platform allows server-side components to service AJAX requests from browsers. Looking forward, the exam will be refreshed in sympathy with the release of future JEE versions. If JEE 6 or 7 is released into a world where AJAX is declining in favor of cometd (HTTP continuations), or another way of enhancing the end-user experience for browser-based applications, then expect that technology to be reflected in the questions posed. After all, the exam is written by a team of subject matter experts who construct the questions and answers for Part I based on the current state of play in the Enterprise Java space.

  • + Share This
  • 🔖 Save To Your Account

InformIT Promotional Mailings & Special Offers

I would like to receive exclusive offers and hear about products from InformIT and its family of brands. I can unsubscribe at any time.


Pearson Education, Inc., 221 River Street, Hoboken, New Jersey 07030, (Pearson) presents this site to provide information about products and services that can be purchased through this site.

This privacy notice provides an overview of our commitment to privacy and describes how we collect, protect, use and share personal information collected through this site. Please note that other Pearson websites and online products and services have their own separate privacy policies.

Collection and Use of Information

To conduct business and deliver products and services, Pearson collects and uses personal information in several ways in connection with this site, including:

Questions and Inquiries

For inquiries and questions, we collect the inquiry or question, together with name, contact details (email address, phone number and mailing address) and any other additional information voluntarily submitted to us through a Contact Us form or an email. We use this information to address the inquiry and respond to the question.

Online Store

For orders and purchases placed through our online store on this site, we collect order details, name, institution name and address (if applicable), email address, phone number, shipping and billing addresses, credit/debit card information, shipping options and any instructions. We use this information to complete transactions, fulfill orders, communicate with individuals placing orders or visiting the online store, and for related purposes.


Pearson may offer opportunities to provide feedback or participate in surveys, including surveys evaluating Pearson products, services or sites. Participation is voluntary. Pearson collects information requested in the survey questions and uses the information to evaluate, support, maintain and improve products, services or sites, develop new products and services, conduct educational research and for other purposes specified in the survey.

Contests and Drawings

Occasionally, we may sponsor a contest or drawing. Participation is optional. Pearson collects name, contact information and other information specified on the entry form for the contest or drawing to conduct the contest or drawing. Pearson may collect additional personal information from the winners of a contest or drawing in order to award the prize and for tax reporting purposes, as required by law.


If you have elected to receive email newsletters or promotional mailings and special offers but want to unsubscribe, simply email information@informit.com.

Service Announcements

On rare occasions it is necessary to send out a strictly service related announcement. For instance, if our service is temporarily suspended for maintenance we might send users an email. Generally, users may not opt-out of these communications, though they can deactivate their account information. However, these communications are not promotional in nature.

Customer Service

We communicate with users on a regular basis to provide requested services and in regard to issues relating to their account we reply via email or phone in accordance with the users' wishes when a user submits their information through our Contact Us form.

Other Collection and Use of Information

Application and System Logs

Pearson automatically collects log data to help ensure the delivery, availability and security of this site. Log data may include technical information about how a user or visitor connected to this site, such as browser type, type of computer/device, operating system, internet service provider and IP address. We use this information for support purposes and to monitor the health of the site, identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents and appropriately scale computing resources.

Web Analytics

Pearson may use third party web trend analytical services, including Google Analytics, to collect visitor information, such as IP addresses, browser types, referring pages, pages visited and time spent on a particular site. While these analytical services collect and report information on an anonymous basis, they may use cookies to gather web trend information. The information gathered may enable Pearson (but not the third party web trend services) to link information with application and system log data. Pearson uses this information for system administration and to identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents, appropriately scale computing resources and otherwise support and deliver this site and its services.

Cookies and Related Technologies

This site uses cookies and similar technologies to personalize content, measure traffic patterns, control security, track use and access of information on this site, and provide interest-based messages and advertising. Users can manage and block the use of cookies through their browser. Disabling or blocking certain cookies may limit the functionality of this site.

Do Not Track

This site currently does not respond to Do Not Track signals.


Pearson uses appropriate physical, administrative and technical security measures to protect personal information from unauthorized access, use and disclosure.


This site is not directed to children under the age of 13.


Pearson may send or direct marketing communications to users, provided that

  • Pearson will not use personal information collected or processed as a K-12 school service provider for the purpose of directed or targeted advertising.
  • Such marketing is consistent with applicable law and Pearson's legal obligations.
  • Pearson will not knowingly direct or send marketing communications to an individual who has expressed a preference not to receive marketing.
  • Where required by applicable law, express or implied consent to marketing exists and has not been withdrawn.

Pearson may provide personal information to a third party service provider on a restricted basis to provide marketing solely on behalf of Pearson or an affiliate or customer for whom Pearson is a service provider. Marketing preferences may be changed at any time.

Correcting/Updating Personal Information

If a user's personally identifiable information changes (such as your postal address or email address), we provide a way to correct or update that user's personal data provided to us. This can be done on the Account page. If a user no longer desires our service and desires to delete his or her account, please contact us at customer-service@informit.com and we will process the deletion of a user's account.


Users can always make an informed choice as to whether they should proceed with certain services offered by InformIT. If you choose to remove yourself from our mailing list(s) simply visit the following page and uncheck any communication you no longer want to receive: www.informit.com/u.aspx.

Sale of Personal Information

Pearson does not rent or sell personal information in exchange for any payment of money.

While Pearson does not sell personal information, as defined in Nevada law, Nevada residents may email a request for no sale of their personal information to NevadaDesignatedRequest@pearson.com.

Supplemental Privacy Statement for California Residents

California residents should read our Supplemental privacy statement for California residents in conjunction with this Privacy Notice. The Supplemental privacy statement for California residents explains Pearson's commitment to comply with California law and applies to personal information of California residents collected in connection with this site and the Services.

Sharing and Disclosure

Pearson may disclose personal information, as follows:

  • As required by law.
  • With the consent of the individual (or their parent, if the individual is a minor)
  • In response to a subpoena, court order or legal process, to the extent permitted or required by law
  • To protect the security and safety of individuals, data, assets and systems, consistent with applicable law
  • In connection the sale, joint venture or other transfer of some or all of its company or assets, subject to the provisions of this Privacy Notice
  • To investigate or address actual or suspected fraud or other illegal activities
  • To exercise its legal rights, including enforcement of the Terms of Use for this site or another contract
  • To affiliated Pearson companies and other companies and organizations who perform work for Pearson and are obligated to protect the privacy of personal information consistent with this Privacy Notice
  • To a school, organization, company or government agency, where Pearson collects or processes the personal information in a school setting or on behalf of such organization, company or government agency.


This web site contains links to other sites. Please be aware that we are not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of each and every web site that collects Personal Information. This privacy statement applies solely to information collected by this web site.

Requests and Contact

Please contact us about this Privacy Notice or if you have any requests or questions relating to the privacy of your personal information.

Changes to this Privacy Notice

We may revise this Privacy Notice through an updated posting. We will identify the effective date of the revision in the posting. Often, updates are made to provide greater clarity or to comply with changes in regulatory requirements. If the updates involve material changes to the collection, protection, use or disclosure of Personal Information, Pearson will provide notice of the change through a conspicuous notice on this site or other appropriate way. Continued use of the site after the effective date of a posted revision evidences acceptance. Please contact us if you have questions or concerns about the Privacy Notice or any objection to any revisions.

Last Update: November 17, 2020