You will be redirected in 30 seconds or close now.

ColdFusion Authors: Yakov Fain, Jeremy Geelan, Maureen O'Gara, Nancy Y. Nee, Tad Anderson

Related Topics: ColdFusion

ColdFusion: Article

Designing ColdFusion Applications for Deployment as EAR Files

There are benefits for everyone

Enterprise Application aRchive (EAR) files are a standard and portable manner for packaging applications to be deployed on J2EE application servers, such as Adobe JRun, BEA WebLogic, and IBM WebSphere. An EAR file is, in essence, just a big ZIP file with a special layout of the directory tree inside that contains a full application, see the following code. EAR files have a well-defined format and make Java bytecode truly portable. The same EAR file that we compile and build on our i386 Windows laptop can also run on a 64-CPU mainframe running commercial Unix.

Directory Structure of an EAR file application.ear

  • application.xml
  • contextroot.war
  • CFML source
  • HTML sources
  • CSS
  • images
  • web.xml
  • ColdFusion runtime
As you can see from this directory structure, an EAR file deployment for a ColdFusion application can include both the CFML source code that you write and a complete ColdFusion server runtime. It's important to note that even when stripped of all documentation and images, an EAR file can be quite large - over 50 MB, not including your source code.

In this article you will learn why it is beneficial to deliver your ColdFusion applications using EAR files. We will also explain what to watch out for when you design applications that you are planning to deliver in an EAR file.

ColdFusion MX 7 Enterprise
To try, go to http://www.adobe.com/go/devcenter_cf_try, and to buy, go to: www.adobe.com/go/devcenter_cf_buy.

Note: You will need to install the ColdFusion multiserver installation. This option is available in the licensed Enterprise Edition, the Developer Edition, or in the 30-day trial edition of ColdFusion MX 7. This requires that you download the trial or purchase the Enterprise, Evaluation, or Developer Edition. You must select "multiserver configuration" during the installation process.

Apache Ant
Download Apache Ant from http://ant.apache.org/.

Prerequisite Knowledge

  • Basic understanding of ColdFusion
  • Basic J2EE knowledge
Advantages of EAR Files
There are many reasons for using EAR files to deploy ColdFusion applications for your customers. Not all are applicable to all customers, but there are generally benefits for everyone.

On the business side, J2EE is a standard technology that has a lot of traction. If your customers already have a J2EE environment, ColdFusion will fit in without changes to their infrastructure. If you want, you can even position ColdFusion as a 4GL language for rapid application development. All that the server administrator sees is an EAR file; it may be big but an EAR file is like any other EAR file. This advantage can open a whole new market that was previously the exclusive domain of Java shops.

On the technical side, EAR files can provide more than just a format for delivering your code. Because EAR files can include the complete ColdFusion runtime, you can also package additional components like database drivers and preconfigured ColdFusion runtime settings. This means you can deliver your application to your customer with far fewer instructions for installation and configuration - greatly reducing the risk of a deployment error.

Combined with the J2EE underpinnings, using EAR files makes it easier to deploy your application in more than one instance on one or more servers. You also have the option to combine these instances into a cluster that provides fault-tolerance and increases the scalability of the application you are deploying.

From a support standpoint, we have all been there: a customer reports that the latest patch doesn't work. After several hours of frantic debugging, you discover that the issue is that the customer never installed a previous patch. However, if you deliver your application as an EAR file, you can ensure that the customer has installed the latest version of every file because each EAR file you deliver contains the entire application.

Challenges to Deploying Applications as EAR Files
There are challenges to delivering your application as an EAR file. Some of the aforementioned advantages can, in other contexts, become disadvantages. For instance, because all the code is compiled and packaged in the EAR file, the customer cannot tinker with it. This also means that you cannot tinker with it after preparing it. If you frequently have to add last-minute, one-line adjustments to your code during deployment, you might find yourself at a disadvantage.

Likewise, creating EAR files requires that you own the ColdFusion Enterprise Edition. You can still develop and build your application using ColdFusion Developer Edition on your local host, but for deployment you must own an Enterprise Edition license for every two CPUs on which you deploy your application. EAR deployments will not work on ColdFusion Standard Edition.

The biggest challenge is how your application interacts with its environment. Because you are delivering a self-contained application, you must be sure to put everything in the EAR file - code, HTML, CSS, additional components, and so forth. Deploying the application should require as little configuration as possible, both to make it easier for your customer and to reduce the chance of something going wrong.

For interaction with the Web server, the most important issue is that you pick the right context-root. The context-root is the subdirectory under which the application is located. By selecting different context-roots, you can deploy multiple applications on one Website. Putting your application in a subdirectory also enables you to handle uploaded user content gracefully (such as avatars on a forum): you can upload them to a sibling directory of the application so the Web server can process them directly. Don't be greedy and use / as the context-root. Because you don't know if the person who deploys your application is going to use an empty J2EE server instance or not, you should develop your application to always run inside a context-root. All paths in your application should be relative to this context-root. When you create your application, choose a context-root so that the name is unique on the deployment server; don't use any common names, such as "admin."

Some of the challenges require you to think about your application in a whole new way. When you package your application as an EAR file, the J2EE server has to expand the application before it can run it. Some J2EE servers, like JRun, do so automatically, which adds some overhead the first time it starts. Others, like WebSphere, require the server administrator to expand the EAR file manually when deploying on it. J2EE servers that expand the EAR file automatically do so to a temporary directory and start the application from there.

One side-effect of this is that the application no longer knows where the EAR file is located; the application knows only the temporary directory to which it was extracted. As a result, when you change something using the ColdFusion Administrator, it ends up in the temporary directory and not in the EAR file. Therefore, if the server administrator moves the EAR file from one server to another, the application will lose any changes that you have made using the ColdFusion Administrator. Even worse, if the operating system deletes all temporary files upon reboot, you will lose all your changes to the ColdFusion Administrator just by rebooting the system. Luckily, this is largely a theoretical problem. Still, if possible, deploy your application as an expanded EAR file. Be mindful of this issue, because even when deploying an expanded EAR file, it will affect your settings when the server administrator moves the EAR or you release a new version.

Another way this becomes a problem is in the use of ColdFusion mappings. When ColdFusion starts from the temporary directory, it automatically updates its internal mapping to CFIDE to point to the temporary directory from which it is executed. All the other mappings will not be updated, however.

More Stories By Jochem van Dieten

Jochem van Dieten is longtime ColdFusion developer and Adobe Community Expert (formerly Team Macromedia) member for ColdFusion. He is currently working on delivery automation and black-box testing at Prisma IT (www.prisma-it.com).

More Stories By Mark van Hedel

Mark van Hedel is an Advanced Certified ColdFusion MX7 Developer and MCI at Prisma IT. He is currently working on automating the ColdFusion development process and creating object-driven applications.

Comments (1) View Comments

Share your thoughts on this story.

Add your comment
You must be signed in to add a comment. Sign-in | Register

In accordance with our Comment Policy, we encourage comments that are on topic, relevant and to-the-point. We will remove comments that include profanity, personal attacks, racial slurs, threats of violence, or other inappropriate material that violates our Terms and Conditions, and will block users who make repeated violations. We ask all readers to expect diversity of opinion and to treat one another with dignity and respect.

Most Recent Comments
SYS-CON Brazil News Desk 06/28/06 03:43:51 PM EDT

Enterprise Application archive (EAR) files are a standard and portable manner for packaging applications to be deployed on J2EE application servers, such as Adobe JRun, BEA WebLogic, and IBM WebSphere. An EAR file is, in essence, just a big ZIP file with a special layout of the directory tree inside that contains a full application, see the following code. EAR files have a well-defined format and make Java bytecode truly portable. The same EAR file that we compile and build on our i386 Windows laptop can also run on a 64-CPU mainframe running commercial Unix.

IoT & Smart Cities Stories
In an era of historic innovation fueled by unprecedented access to data and technology, the low cost and risk of entering new markets has leveled the playing field for business. Today, any ambitious innovator can easily introduce a new application or product that can reinvent business models and transform the client experience. In their Day 2 Keynote at 19th Cloud Expo, Mercer Rowe, IBM Vice President of Strategic Alliances, and Raejeanne Skillern, Intel Vice President of Data Center Group and G...
Discussions of cloud computing have evolved in recent years from a focus on specific types of cloud, to a world of hybrid cloud, and to a world dominated by the APIs that make today's multi-cloud environments and hybrid clouds possible. In this Power Panel at 17th Cloud Expo, moderated by Conference Chair Roger Strukhoff, panelists addressed the importance of customers being able to use the specific technologies they need, through environments and ecosystems that expose their APIs to make true ...
The current age of digital transformation means that IT organizations must adapt their toolset to cover all digital experiences, beyond just the end users’. Today’s businesses can no longer focus solely on the digital interactions they manage with employees or customers; they must now contend with non-traditional factors. Whether it's the power of brand to make or break a company, the need to monitor across all locations 24/7, or the ability to proactively resolve issues, companies must adapt to...
We are seeing a major migration of enterprises applications to the cloud. As cloud and business use of real time applications accelerate, legacy networks are no longer able to architecturally support cloud adoption and deliver the performance and security required by highly distributed enterprises. These outdated solutions have become more costly and complicated to implement, install, manage, and maintain.SD-WAN offers unlimited capabilities for accessing the benefits of the cloud and Internet. ...
Business professionals no longer wonder if they'll migrate to the cloud; it's now a matter of when. The cloud environment has proved to be a major force in transitioning to an agile business model that enables quick decisions and fast implementation that solidify customer relationships. And when the cloud is combined with the power of cognitive computing, it drives innovation and transformation that achieves astounding competitive advantage.
DXWorldEXPO LLC announced today that "IoT Now" was named media sponsor of CloudEXPO | DXWorldEXPO 2018 New York, which will take place on November 11-13, 2018 in New York City, NY. IoT Now explores the evolving opportunities and challenges facing CSPs, and it passes on some lessons learned from those who have taken the first steps in next-gen IoT services.
Founded in 2000, Chetu Inc. is a global provider of customized software development solutions and IT staff augmentation services for software technology providers. By providing clients with unparalleled niche technology expertise and industry experience, Chetu has become the premiere long-term, back-end software development partner for start-ups, SMBs, and Fortune 500 companies. Chetu is headquartered in Plantation, Florida, with thirteen offices throughout the U.S. and abroad.
DXWorldEXPO LLC announced today that ICC-USA, a computer systems integrator and server manufacturing company focused on developing products and product appliances, will exhibit at the 22nd International CloudEXPO | DXWorldEXPO. DXWordEXPO New York 2018, colocated with CloudEXPO New York 2018 will be held November 11-13, 2018, in New York City. ICC is a computer systems integrator and server manufacturing company focused on developing products and product appliances to meet a wide range of ...
René Bostic is the Technical VP of the IBM Cloud Unit in North America. Enjoying her career with IBM during the modern millennial technological era, she is an expert in cloud computing, DevOps and emerging cloud technologies such as Blockchain. Her strengths and core competencies include a proven record of accomplishments in consensus building at all levels to assess, plan, and implement enterprise and cloud computing solutions. René is a member of the Society of Women Engineers (SWE) and a m...
SYS-CON Events announced today that DatacenterDynamics has been named “Media Sponsor” of SYS-CON's 18th International Cloud Expo, which will take place on June 7–9, 2016, at the Javits Center in New York City, NY. DatacenterDynamics is a brand of DCD Group, a global B2B media and publishing company that develops products to help senior professionals in the world's most ICT dependent organizations make risk-based infrastructure and capacity decisions.