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

Building Generic Maintenance Interfaces

Sparing yourself an awful lot of tedious work

When the March 2006 issue of CFDJ arrived, I had just begun working on the maintenance interfaces for the support tables of a new system. There are many of these tables, and implementing the associated maintenance routines looked set to consume a lot of time.

I had just finished implementing DAOs for the first of the support forms when I came across Nic Tunney's article on ObjectBreeze. ObjectBreeze was going to save me a lot of time on implementation - and spare me an awful lot of tedious work building DAOs for each table.

ObjectBreeze saved me so much time it got me to thinking… Would it be possible to implement the user interfaces generically, in the same way that ObjectBreeze implements our data model? And if we have a consistent, generic interface to access a data model, can we leverage that interface in the view and controller tiers too? The controller tier seems simple enough - for a simple maintenance form it merely needs to actuate the CRUD methods of the DAO. As far as the view tier goes, if it knew what the data model looked like, it shouldn't be difficult. The potential benefits would be enormous - I could concentrate my time on the difficult tasks of aggregating data and implementing business logic without worrying about data access or user interfaces.

Building the Basics
For this article we're going to put together a fictitious system for a hypothetical racing club. This club needs to track the drivers, teams, and cars that enter club races in various classes. Figure 1 details our data model. We have tables for each object - drivers, cars, teams, and classes. A car belongs to a single team, races in a single class, and is driven by a single driver. Drivers can drive any number of cars in different classes for different teams. Teams can own any number of cars, and classes can contain any number of cars.

Let's start with the drivers. They're one of the simplest objects because they don't contain any references to other objects (tables). The club is interested in tracking a driver's first and last name and his nationality. First we'll set up our controller (drivers.cfm). This will be the only file that the browser requests when manipulating a driver object. Our controller is essentially a switch statement that interprets a form parameter called controlMethod. Our controller supports the standard CRUD operations - create (add), read (edit), update, and delete operations, plus a list operation. Each operation involves a database operation and a user interface to render the results. The list operation will retrieve all of the drivers and display them in a grid, and the edit operation retrieves one driver and outs his details in a form for editing. Create is similar to edit except that it creates a new driver record. Update applies the results of a create or edit operation and delete removes a driver's data from the database. ObjectBreeze is used to handle the data model.

Each method that has to present data to the user also contains a call to the custom tag responsible for building the view. There's a tag for displaying lists (grid) and for editing a single record (detail). Since these templates are going to be generic, I've put them in a directory called genericUI. A CFMODULE call is used to invoke the generic code.

The Views
The maintenance for the drivers' table is a typical table maintenance application - a list of items and a detail form for editing an individual item. The generic grid template will display our list of items with controls to enable adding and deleting records, and a control to select an item for editing. To do this we have to tell the grid control which fields we want displayed, what the captions for those fields should be, and the data to be displayed. Using that information it's a pretty simple matter of looping over the list of captions to create the grid header. A two-dimensional loop displays the requested fields for each row of data.

The detail form is similar to the grid. For each field in the data model, we generate a table row containing a label and a textbox to edit the corresponding field. Arguments to our custom tag are similar to the grid except that we're passing a single data object.

See Listing 1 for the code we've built so far.

So how does it work? Not bad for a first stab. We've got a grid containing a list of drivers. We've got links for adding, editing, and deleting drivers. It definitely isn't perfect - there are a couple shortcomings we'll want to address. The first of these shortcomings is that the controller template is specific to the drivers' table. Before we can really reuse our code we'll want to build a generic controller template.

The Controller
Fortunately the task of converting the controller template is fairly simple. We want to call the controller as a custom tag, so instead of looking at form variables for our parameters we're going to be looking at attributes. We'll also have to tell the controller what fields we want displayed, and what their associated captions are. We'll also pass the form scope into the controller. Then we modify our custom tag calls to use these attributes instead of our hard-coded field lists. Our generic controller gets a new name - genericmasterdetail.cfm - and it moves into the genericUI folder.

The page that the browser invokes now becomes very simple - just a call to genericmasterdetail with the proper parameters. When we test our new drivers.cfm page in the browser, everything looks and functions exactly as before. Now we're ready to really leverage what we've built. The classes and team tables are both simple tables, similar in structure to the drivers' table. We make copies of the drivers.cfm file, change the parameters we pass to genericmasterdetail, and presto - fully functional maintenance forms for drivers, teams, and classes. I've done a little preprocessing to make things a bit neater. For example, I've included logic in classes.cfm to instruct our generic user interface to display only the class name during the list operation and all three fields during add or edit operations. See Listing 2 for the updated code.

Object Composition
The objects we've worked with so far are very simple in that all of the data they require is in one table. Usually, we're not that lucky; we often need data from multiple tables. ObjectBreeze supports models like these through composite objects. ObjectBreeze gives us a nice set of features for working with composite objects - we use the containsOne() or containsMany() methods to register the relationships between our tables with ObjectBreeze and it takes care of our database interactions for us.

Introducing composition into our generic user interfaces poses two problems. The first is how to tell the controller code to create a compound data object for us. The second is how to deal with this data in the user interface.

The second question is actually the easier of the two to answer. If we have a "contains one" relationship, such as the one between a team and a car, we can use a list box control to update that relationship. If we have a "contains many" relationship, we can use a cross-select to select the related items. Of course we'll have to know the relationship between the parent and children to know how to handle each item, but we have to describe that relationship to the controller to get the data objects configured properly in the first place.

XML to the Rescue
XML is the perfect choice for describing data to our generic user interfaces. It also makes it easy to enhance our code without making changes to the way it gets called. We're going to work with the racecars table for our first example. Cars are driven by a driver, entered in a class, and owned by a team. That is to say that there is a "contains one" relationship between our racecars object and the team, classes, and drivers objects.

The XML document that describes the racecars' object to genericmasterdetail is in Listing 3. The document describes the data model (datamodel element and children), the grid view (grid element), and the detail view (detail element). We'll feed this document into our genericmasterdetail custom tag and from there into the grid and detail custom tags. These tags have changed in several different ways. First, the arguments have changed. The form scope still gets passed into genericmasterdetail, grid, and detail but the configuration document has replaced the other arguments. All the references to the old arguments were updated to look at the configuration document instead. A new custom tag - uiformelements - has been created to handle the display of the individual form elements. Finally, two helper functions have been created to help us manage composite data access objects.

Listing 3 contains the racecars' XML document and the helper functions configureDAO() and getProperty().

All of these upgrades buy us a lot of functionality. We've moved quite a ways beyond simple forms. We can now add, update, and delete records in a wide variety of formats with just a few lines of XML.

More Stories By Craig Drabik

Craig Drabik is a senior programmer with the State University of New York at Buffalo. He is a Macromedia certified ColdFusion developer who has been working in ColdFusion since version 4.51.

Comments (2) 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
Ron Phillips 06/12/06 03:12:20 PM EDT

Well, the download works fine. Very nice!

I'm a little concerned about using a modified version of objectbreeze -- is Nick going to change it in the next release, or what's the status?


Craig Drabik 06/08/06 04:47:21 PM EDT

You can download a complete archive of all the code, and working examples for each segment, as well as the completed framework at http://www.acsu.buffalo.edu/~cjdrabik/racecars_sample.zip

Thanks for reading!

@ThingsExpo Stories
22nd International Cloud Expo, taking place June 5-7, 2018, at the Javits Center in New York City, NY, and co-located with the 1st DXWorld Expo will feature technical sessions from a rock star conference faculty and the leading industry players in the world. Cloud computing is now being embraced by a majority of enterprises of all sizes. Yesterday's debate about public vs. private has transformed into the reality of hybrid cloud: a recent survey shows that 74% of enterprises have a hybrid cloud ...
In his keynote at 19th Cloud Expo, Sheng Liang, co-founder and CEO of Rancher Labs, discussed the technological advances and new business opportunities created by the rapid adoption of containers. With the success of Amazon Web Services (AWS) and various open source technologies used to build private clouds, cloud computing has become an essential component of IT strategy. However, users continue to face challenges in implementing clouds, as older technologies evolve and newer ones like Docker c...
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 ...
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.
Cloud-enabled transformation has evolved from cost saving measure to business innovation strategy -- one that combines the cloud with cognitive capabilities to drive market disruption. Learn how you can achieve the insight and agility you need to gain a competitive advantage. Industry-acclaimed CTO and cloud expert, Shankar Kalyana presents. Only the most exceptional IBMers are appointed with the rare distinction of IBM Fellow, the highest technical honor in the company. Shankar has also receive...
Michael Maximilien, better known as max or Dr. Max, is a computer scientist with IBM. At IBM Research Triangle Park, he was a principal engineer for the worldwide industry point-of-sale standard: JavaPOS. At IBM Research, some highlights include pioneering research on semantic Web services, mashups, and cloud computing, and platform-as-a-service. He joined the IBM Cloud Labs in 2014 and works closely with Pivotal Inc., to help make the Cloud Found the best PaaS.
In his Opening Keynote at 21st Cloud Expo, John Considine, General Manager of IBM Cloud Infrastructure, led attendees through the exciting evolution of the cloud. He looked at this major disruption from the perspective of technology, business models, and what this means for enterprises of all sizes. John Considine is General Manager of Cloud Infrastructure Services at IBM. In that role he is responsible for leading IBM’s public cloud infrastructure including strategy, development, and offering m...
DXWorldEXPO LLC announced today that All in Mobile, a mobile app development company from Poland, will exhibit at the 22nd International CloudEXPO | DXWorldEXPO. All In Mobile is a mobile app development company from Poland. Since 2014, they maintain passion for developing mobile applications for enterprises and startups worldwide.
Headquartered in Plainsboro, NJ, Synametrics Technologies has provided IT professionals and computer systems developers since 1997. Based on the success of their initial product offerings (WinSQL and DeltaCopy), the company continues to create and hone innovative products that help its customers get more from their computer applications, databases and infrastructure. To date, over one million users around the world have chosen Synametrics solutions to help power their accelerated business or per...
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. ...
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.
Dion Hinchcliffe is an internationally recognized digital expert, bestselling book author, frequent keynote speaker, analyst, futurist, and transformation expert based in Washington, DC. He is currently Chief Strategy Officer at the industry-leading digital strategy and online community solutions firm, 7Summits.
Bill Schmarzo, author of "Big Data: Understanding How Data Powers Big Business" and "Big Data MBA: Driving Business Strategies with Data Science," is responsible for setting the strategy and defining the Big Data service offerings and capabilities for EMC Global Services Big Data Practice. As the CTO for the Big Data Practice, he is responsible for working with organizations to help them identify where and how to start their big data journeys. He's written several white papers, is an avid blogge...
I think DevOps is now a rambunctious teenager - it's starting to get a mind of its own, wanting to get its own things but it still needs some adult supervision," explained Thomas Hooker, VP of marketing at CollabNet, in this SYS-CON.tv interview at DevOps Summit at 20th Cloud Expo, held June 6-8, 2017, at the Javits Center in New York City, NY.
"MobiDev is a software development company and we do complex, custom software development for everybody from entrepreneurs to large enterprises," explained Alan Winters, U.S. Head of Business Development at MobiDev, in this SYS-CON.tv interview at 21st Cloud Expo, held Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA.
Major trends and emerging technologies – from virtual reality and IoT, to Big Data and algorithms – are helping organizations innovate in the digital era. However, to create real business value, IT must think beyond the ‘what’ of digital transformation to the ‘how’ to harness emerging trends, innovation and disruption. Architecture is the key that underpins and ties all these efforts together. In the digital age, it’s important to invest in architecture, extend the enterprise footprint to the cl...
Data is the fuel that drives the machine learning algorithmic engines and ultimately provides the business value. In his session at Cloud Expo, Ed Featherston, a director and senior enterprise architect at Collaborative Consulting, discussed the key considerations around quality, volume, timeliness, and pedigree that must be dealt with in order to properly fuel that engine.
Two weeks ago (November 3-5), I attended the Cloud Expo Silicon Valley as a speaker, where I presented on the security and privacy due diligence requirements for cloud solutions. Cloud security is a topical issue for every CIO, CISO, and technology buyer. Decision-makers are always looking for insights on how to mitigate the security risks of implementing and using cloud solutions. Based on the presentation topics covered at the conference, as well as the general discussions heard between sessio...
IoT is rapidly becoming mainstream as more and more investments are made into the platforms and technology. As this movement continues to expand and gain momentum it creates a massive wall of noise that can be difficult to sift through. Unfortunately, this inevitably makes IoT less approachable for people to get started with and can hamper efforts to integrate this key technology into your own portfolio. There are so many connected products already in place today with many hundreds more on the h...
No hype cycles or predictions of zillions of things here. IoT is big. You get it. You know your business and have great ideas for a business transformation strategy. What comes next? Time to make it happen. In his session at @ThingsExpo, Jay Mason, Associate Partner at M&S Consulting, presented a step-by-step plan to develop your technology implementation strategy. He discussed the evaluation of communication standards and IoT messaging protocols, data analytics considerations, edge-to-cloud tec...