Home > Articles > Programming > Java

The Components of Java Message Service

In this sample chapter, Brian Cavaness and Chuck Keeton cover the following topics: the components of the JMS architecture, two JMS message models, the JMS interfaces, details of a JMS message, message selection and filtering, the JMS Point-to-Point model, the JMS Publish/Subscribe model, synchronous versus asynchronous messaging, message persistence, using transactions with JMS, and using JMS with Enterprise JavaBeans.
This sample chapter is excerpted from Special Edition Using Enterprise JavaBeans 2.0, by Chuck Cavaness and Brian Keeton.
This chapter is from the book

Introduction to Messaging

Messaging applications, or as they are sometimes called, Message Oriented Middleware (MOM) products, have been used for quite some time. These messaging products help applications that normally are not connected to one another structurally communicate with each other. In applications that aren't using a messaging product, this communication might be performed using sockets, RMI, or in various other ways. A few problems are associated with communicating between applications using one of these approaches.

One of the problems is that each side involved in the communication might have direct knowledge about one another. Each side is aware of the other with respect to the transport protocol and other low-level details. This knowledge is known as a tight coupling. It would be more flexible if the two sides weren't so tightly coupled. This way, if something changed on either side, the other side might not be affected. Another problem is that it's hard to perform asynchronous messaging with sockets or RMI. Asynchronous communication is where a response is not immediately expected or returned. The alternative approaches just mentioned, such as sockets or RMI, are types of synchronous communication.

Message-oriented middleware can help reduce the coupling and complexity of allowing applications or components to communicate with one another asynchronously. It's also designed to help interoperability between applications, which is very important when building enterprise applications.

What Is Message-Oriented Middleware?

Message-oriented middleware was designed to decouple the applications or components and allow them to communicate with one another by exchanging messages asynchronously. These messages can be things such as event notifications, application data, request for services, or even objects. Any type of information that needs to be communicated from one application to another is done by passing a message to the receiving system. As you'll see later in this chapter, various types of messages can be passed from one application to another.

Although messages generally can be sent in either direction, certain names are given to the application or component that is sending or receiving a message. The component that creates or produces a message is referred to as a producer. The application or component that receives a message is called a consumer. It's possible for an application to be both a producer and a consumer of messages, but for a given transfer of information, one side must produce the message and another side must consume it. A benefit of separating the producing and the consuming of messages is that the producer and consumer only really need to agree on the format of the message. Each side doesn't need to worry about how the message is transported. To make this possible, a message is not sent directly from a producer to the consumer. As we'll see later in this chapter, how it makes its way to the consumer depends on which type of messaging model you choose for your application. Figure 10.1 illustrates a generic messaging scenario.

Figure 10.1 An application communicating through messaging contains a producer and a consumer.

Java Message Service as a Message-Oriented Middleware

Although the EJB 2.0 Specification does not cover messaging, it is part of the Java Message Service (JMS) specification and is so fundamental to the Enterprise JavaBeans API that it would be deficient not to cover it in any serious discussion on the subject. Because many enterprise applications will use some level of messaging, it's a good idea to understand the concepts. You also will need to be familiar with the Java Message Service (JMS) APIs before understanding the new message-driven bean that has been added to the EJB 2.0 Specification.

See "Message-Driven Beans," p. 315 for more information on the new enterprise bean added to EJB 2.0.

Differences Among JMS Implementations

Another important fact should be pointed out. JMS is not an implementation of a message-oriented middleware. In fact, it's really nothing more than a specification for describing how messages should be produced and consumed in a Java enterprise application. By itself, it provides no functionality. As with other APIs that we have already discussed, the API or interfaces are separate from the implementation. This gives the benefit of describing in detail what the user view should be, while at the same time allowing vendors to implement the details however they want. As long as the vendor adheres to the JMS specification, a user shouldn't have to worry too much about how the implementation is constructed. The point of hiding the implementation from the client and exposing only the JMS APIs is to hide the details from the users that want a higher-level API and also to ensure portability among implementations.

If a vendor implements the JMS specification and adheres to it completely, there is typically no problem developing portable JMS applications and switching between vendors. As with the rest of the specifications in the Java 2 Enterprise Edition (J2EE), JMS has a version number that identifies that current release of the specification. The current JMS specification is 1.0.2. If you write an application based on this or any newer specification, you must ensure that the vendor whose JMS implementation you are using adheres to this level of the specification. You can download the latest JMS specification at the following URL:


Many vendors provide an implementation for the JMS specification. Some are included along with a complete or partial implementation of the entire J2EE suite of technologies. Table 10.1 is a list of vendors who provide a commercial implementation of the JMS specification.

Table 10.1 Vendors Who Provide a Commercial JMS Implementation



JRUN Server


BEA Systems, Inc.


Fiorano Software












Progress Software


SAGA Software, Inc.


SoftWired Inc.


Sun (Java Message Queue)


SpiritSoft, Inc.






Venue Software


There are also several open-source JMS projects. Table 10.2 lists a few of them.

Table 10.2 Partial List of Open-Source JMS Projects



ObjectCube, Inc.






Many other vendors endorse the JMS API. The following URL provides a more exhaustive listing:


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