Welcome!

Adobe Flex Authors: Matthew Lobas, PR.com Newswire, Shelly Palmer, Kevin Benedict

Related Topics: Adobe Flex

Adobe Flex: Article

Code Reuse - Pros and Cons

Notes of a soldier from the oh-so-bloody front

Depending on the scope of your project, you may have the opportunity for code reuse. The reasons you might want to do so are two-fold. First, you reduce duplication of efforts. If you have already created a hyperlink enabled CellRenderer for your DataGrid once, why do it again? Second, you create, or build upon, an ever growing utility code base. While it may not be in the "utils" package per se, you'll soon end up with re-usable events, common GUI controls and widgets, and yes even utility classes. Whether by merely being in a different folder means the client doesn't own it is up to you or your sales team.

Duplication Killed on Sight
On the current project I'm on, we re-use a LOT. My eagle-eye boss the architect head-shots any duplication he sees. Thus, we the developers have been trained to quickly identify something we create for re-use if possible and either plan accordingly when building it, or go in search of "spare parts" from existing classes throughout the main code-base for re-use. Our main base consists of 3 company names, each containing at least 3 individual "products". The first question I ask my fellow developers, and they in return, when starting to build something new is, "Has this been done before?" Re-inventing the wheel has no place in a production cycle unless you can clearly point out how the original wheel design was flawed, can be done better, and done so in a reasonable time frame approved by the client.

This also helps ensure I don't code something similar to what has already been done. To the client's point of view, they already paid for a LoginForm...why should they have to pay for a new one when all they want is for it to be green instead of blue?

"Dan, the login form's blue by default, but the mockups I have here are green."

"That's because the View using it sets it to blue; it has a color property that is an inherited style; you can style it yourself, just do color='#yourcolor'."

"Oh... nice!"

Suddenly, I spend 10 minutes finding the file and including it, setting its color, registering for its login event, and building a test file to see it in action. This instead of 4 hours doing the same building a green one. Take how much you make per hour, multiply by 4, and then subtract what you make in 15 minutes. That difference is what you just saved the client by "asking a question." I've learned the hard way to ask a lot of questions to the point of being annoying and forcing people to repeat themselves.

The same goes for building more complex things that have to be unique to a point. The most common example which I already alluded to is the CellRenderer. This is a class commonly utilized in Flash and Flex development to customize what's showing in a DataGrid column; each row will render the custom class instead of the default and pass it an item to render. Since every DataGrid on a project is unique, you inevitably end up with a multitude of cellrenderer classes. These classes are, at least for me, notoriously hard to share so you attempt to make them as generic as possible so others can either use them as is, or do the most common thing and extend your base one to customize it to their needs.

This is an important point. The 30 or so lines of code that are required to setup a cellrenderer are suddenly already written for you, and the other developers on your team. This is a great place where inheritance really works and should be exploited. It doesn't stop there; some of the cellrenderers created could be used elsewhere as well. The only challenge is how they're designed from a visual standpoint. Styles can handle a lot, but most designers I have had the pleasure of working with have a knack of making something unique, and unique isn't always re-usable. You can either find a happy compromise with your designers, or respect their artistic integrity and recognize the fact that that they design is truly made specifically for a certain need and shouldn't be made re-usable.

Con of a Component Buffet
The first con to reusing already-built components hits the design side hardest. One of the biggest gripes people have had with any Flash/Flex component is styling and skinning. While CSS styling has come a long way in Flex 2, there are always those times where the artist (in you or beside you) goes, "It's just not right..." Sometimes extending the base component just for styling purposes is the best repose since the base component isn't muddied with application specific styling routines.

The second con which can really come to the forefront in teams is you just don't like the component. Any developer who isn't apprehensive about using a component they didn't write makes me nervous. You trust code you didn't write? Sometimes you don't have a choice or recognize the alternatives are unacceptable. We're all human, and have our coding styles, and even if notation and other rules are enforced on your team, you can still dislike the implementation of something. This should be in the back of your mind when creating code for reuse as well. How will my code be perceived? The base rules such as encapsulation should be followed, but obviously there are other esoteric and styles of implementation that can drastically impact your involvement to ensure others spend very little of theirs getting acclimated to how it works for example.

Sum Greater Than Its Parts
For components that are made up of other components via Composition, I'll ask my fellow developers if the pieces I need are already built. For example, if I'm creating a form, I'll re-use the extended TextInput's we have. For the above CellRenderer, if it has to display a Date, I'll set the labelFunction to utilize the DateUtils class we have which will take a regular Date object and make it look like, "Tue 5/23/2006". I didn't have to write the base class of the CellRenderer and I didn't have to write a class to format dates, I just had to use the class. I've been doing the same thing for a long time without really thinking about it. For example, I take for example I can just "use a DataGrid" and "extend it with a CellRenderer". Macromedia/Adobe spent a lot of time developing one that could be reusable. Naturally, there comes a point where something is coded to business rules or a certain design, and the pragmatist in me knows when to stop trying to overdo it.

Let's turn it up a notch, though. What if you've built a DataGrid that has custom cellrenders, text fields on the bottom to filter it, and is tied to a specific ValueObject it knows how to display, and display well? Can you re-use that? Absolutely! Just because you don't right now doesn't mean you won't later. You should typically design with the intention to do so, but not so much you don't ever actually complete anything beyond a pimped out skeleton. Adamantine ingots may have great potential, but are merely blocks of immobile metal until merged with, say, a regenerative Canadian supersoldier's skeleton. Put what you write to use sooner rather than later.

This is where code reuse really shines. You're near mini-application status component which does a lot is now re-used by your team. If the components within it follow normal styling rules and expose their innards to those who wish to extend it, your golden if certain custom styling needs to be applied. What could possibly be a con about this?

Package Structure
Package structure. Package structure, for those who don't know, is how code is organized into folders. Folders are called "packages" because they have code and other packages in them depending on how deeply you nest your code. Code is placed into class files (.as or .mxml) and placed into folders. The typical naming scheme goes deployment type, company, project, and then regular code. This can take the form of com.adobe.utils.DateUtils where you have a com folder that contains an adobe folder which in turn contains a utils folder which contains the DateUtils.as file. You then import the class or "package path" into your code and the class DateUtils, and your code will know what folder to look in from the import statement.

Some projects do get large enough where you do in fact have more than one project folder. Code re-use is typically thought of through Views of some sort client developers. There is however, no reason you cannot re-use Views across projects. You just reference the package path. The pros are, work effort utilized on a project can be re-used on other projects. Sometimes you can plan for this re-use, and sometimes it's a pleasant surprise.

Licenses
I suppose, depending on the license, that you could use it for different companies as well, but each license has specific rules on how code is used. Creative Commons is pretty simple; just keep the author's name in the code unless she/he says otherwise. From that point forward, you can modify and re-modify to your heart's content with no license fee. Others are a lot weirder. Some companies require you supply them source code. Some don't even know what source code is. Still others own everything you write while in their presence, thus preventing you from using any of your own re-usable stuff. A common tactic I've seen is to have your company's name next to the client's company name. All common views and utility classes are put in yours, and the custom developed work is put in the client's package path.

Global Ramifications
That last point is another important point. Code by residing in your company's folder its very nature has a very special, and important place; it's created for re-use. On the current project, or projects, it's re-used in many places. While all uses of it are immediately improved upon once you improve the base component, thus improving the whole project, this can have unforeseen consequences as well.

For example, you build your own List control to render extremely unique rows that animate instead of simply refreshing. In practice, you see that it is extremely slow, especially when multiple instances of it are used. You go in and re-factor it, finding many places in the code you can speed up. Suddenly, the entire app speeds up where those components are used.

One of these changes was to expose a method for updating one specific item versus all of them when a piece of data changes. This is accomplished via a new method. That's a bad thing. Suddenly all the classes that use it now have to update themselves just to access one of the new optimizations.

Touching a point I brought up earlier, sharing views between projects - the problem with that is that, if you change a view in one project, you've just affected the other one. Code that was seemingly "working" you just broke, and you didn't know it because you were never compiling, nor even involved in the other project. The important point here is: if you are going to identify something as re-usable, make it so, and put it into a global package such as your company's folder, or another aptly named common folder. Developers who go into the code in those packages know full well the ramifications of what their changes could do, for good or ill.

Tool Shed
When I got my first apartment, I had one screwdriver and one small Phillips head to my name. Now that I own a house, I have a small utility closet full of tools. I'm sure by the time I'm eighty, I'll need a tool shed to hold them all. The same can be said about your "common" code base: you'll find over time that it'll grow into an extremely useful and portable set of code. Remember, you don't have to write it all yourself, nor does your team. There's a lot of free code on the Net that you can test yourself, and then incorporate. This'll save you from having to create a hammer before you can use said hammer every project; going in, you'll be equipped to the teeth, and you'll come out with more ammo than you started with.

Summary
The greater the size of the project, and/or the more frequenct the projects,the more important reusing code becomes. Making the most of a developer's time spent coding is done this way, and allows many others to benefit from that work for months, even years to come. For example, I've been using the same preloader in Flash for 3 years, written in ActionScript 1 in Flash 5. I still customize the colors, though, every time.

With reuse comes great responsibility. If you are designating something as reusable, it can be quite frightening to realize that a lot of others are suddenly depending on this pinnacle piece of code. That is a risk worth taking, and a strength you should prey upon. As long as you recognize the dependencies, and reduce coupling, you'll start gaining a lot more efficiency from the time you and your team spend coding.

When I first learned about reuse, I could never get it to work in practice. I either ran out of time and copy-pasted or my original design was perceived to me as being "flawed" even though it worked perfectly fine. I was just being unreasonable. Keep it simple, and you'll do fine.

More Stories By Jesse Randall Warden

Jesse R. Warden, a member of the Editorial Board of Web Developer's & Designer's Journal, is a Flex, Flash and Flash Lite consultant for Universal Mind. A professional multimedia developer, he maintains a Website at jessewarden.com where he writes about technical topics that relate to Flash and Flex.

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 India News Desk 07/17/06 10:44:08 AM EDT

Depending on the scope of your project, you may have the opportunity for code reuse. The reasons you might want to do so are two-fold. First, you reduce duplication of efforts. If you have already created a hyperlink enabled CellRenderer for your DataGrid once, why do it again? Second, you create, or build upon, an ever growing utility code base. While it may not be in the 'utils' package per se, you'll soon end up with re-usable events, common GUI controls and widgets, and yes even utility classes. Whether by merely being in a different folder means the client doesn't own it is up to you or your sales team.

@ThingsExpo Stories
DevOps is often described as a combination of technology and culture. Without both, DevOps isn't complete. However, applying the culture to outdated technology is a recipe for disaster; as response times grow and connections between teams are delayed by technology, the culture will die. A Nutanix Enterprise Cloud has many benefits that provide the needed base for a true DevOps paradigm.
You think you know what’s in your data. But do you? Most organizations are now aware of the business intelligence represented by their data. Data science stands to take this to a level you never thought of – literally. The techniques of data science, when used with the capabilities of Big Data technologies, can make connections you had not yet imagined, helping you discover new insights and ask new questions of your data. In his session at @ThingsExpo, Sarbjit Sarkaria, data science team lead ...
The Internet of Things will challenge the status quo of how IT and development organizations operate. Or will it? Certainly the fog layer of IoT requires special insights about data ontology, security and transactional integrity. But the developmental challenges are the same: People, Process and Platform and how we integrate our thinking to solve complicated problems. In his session at 19th Cloud Expo, Craig Sproule, CEO of Metavine, demonstrated how to move beyond today's coding paradigm and sh...
Big Data, cloud, analytics, contextual information, wearable tech, sensors, mobility, and WebRTC: together, these advances have created a perfect storm of technologies that are disrupting and transforming classic communications models and ecosystems. In his session at @ThingsExpo, Erik Perotti, Senior Manager of New Ventures on Plantronics’ Innovation team, provided an overview of this technological shift, including associated business and consumer communications impacts, and opportunities it m...
WebRTC is about the data channel as much as about video and audio conferencing. However, basically all commercial WebRTC applications have been built with a focus on audio and video. The handling of “data” has been limited to text chat and file download – all other data sharing seems to end with screensharing. What is holding back a more intensive use of peer-to-peer data? In her session at @ThingsExpo, Dr Silvia Pfeiffer, WebRTC Applications Team Lead at National ICT Australia, looked at differ...
With major technology companies and startups seriously embracing IoT strategies, now is the perfect time to attend @ThingsExpo 2016 in New York. Learn what is going on, contribute to the discussions, and ensure that your enterprise is as "IoT-Ready" as it can be! Internet of @ThingsExpo, taking place June 6-8, 2017, at the Javits Center in New York City, New York, is co-located with 20th Cloud Expo and will feature technical sessions from a rock star conference faculty and the leading industry p...
SYS-CON Events announced today that IoT Now has been named “Media Sponsor” of SYS-CON's 20th International Cloud Expo, which will take place on June 6–8, 2017, at the Javits Center 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.
SYS-CON Events announced today that WineSOFT will exhibit at SYS-CON's 20th International Cloud Expo®, which will take place on June 6-8, 2017, at the Javits Center in New York City, NY. Based in Seoul and Irvine, WineSOFT is an innovative software house focusing on internet infrastructure solutions. The venture started as a bootstrap start-up in 2010 by focusing on making the internet faster and more powerful. WineSOFT’s knowledge is based on the expertise of TCP/IP, VPN, SSL, peer-to-peer, mob...
The Internet of Things can drive efficiency for airlines and airports. In their session at @ThingsExpo, Shyam Varan Nath, Principal Architect with GE, and Sudip Majumder, senior director of development at Oracle, discussed the technical details of the connected airline baggage and related social media solutions. These IoT applications will enhance travelers' journey experience and drive efficiency for the airlines and the airports.
A strange thing is happening along the way to the Internet of Things, namely far too many devices to work with and manage. It has become clear that we'll need much higher efficiency user experiences that can allow us to more easily and scalably work with the thousands of devices that will soon be in each of our lives. Enter the conversational interface revolution, combining bots we can literally talk with, gesture to, and even direct with our thoughts, with embedded artificial intelligence, whic...
WebRTC sits at the intersection between VoIP and the Web. As such, it poses some interesting challenges for those developing services on top of it, but also for those who need to test and monitor these services. In his session at WebRTC Summit, Tsahi Levent-Levi, co-founder of testRTC, reviewed the various challenges posed by WebRTC when it comes to testing and monitoring and on ways to overcome them.
SYS-CON Events announced today that CA Technologies has been named “Platinum Sponsor” of SYS-CON's 20th International Cloud Expo®, which will take place on June 6-8, 2017, at the Javits Center in New York City, NY, and the 21st International Cloud Expo®, which will take place October 31-November 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. CA Technologies helps customers succeed in a future where every business – from apparel to energy – is being rewritten by software. From ...
In his keynote at 18th Cloud Expo, Andrew Keys, Co-Founder of ConsenSys Enterprise, provided an overview of the evolution of the Internet and the Database and the future of their combination – the Blockchain. Andrew Keys is Co-Founder of ConsenSys Enterprise. He comes to ConsenSys Enterprise with capital markets, technology and entrepreneurial experience. Previously, he worked for UBS investment bank in equities analysis. Later, he was responsible for the creation and distribution of life settle...
In his session at @ThingsExpo, Steve Wilkes, CTO and founder of Striim, will delve into four enterprise-scale, business-critical case studies where streaming analytics serves as the key to enabling real-time data integration and right-time insights in hybrid cloud, IoT, and fog computing environments. As part of this discussion, he will also present a demo based on its partnership with Fujitsu, highlighting their technologies in a healthcare IoT use-case. The demo showcases the tracking of patie...
The explosion of new web/cloud/IoT-based applications and the data they generate are transforming our world right before our eyes. In this rush to adopt these new technologies, organizations are often ignoring fundamental questions concerning who owns the data and failing to ask for permission to conduct invasive surveillance of their customers. Organizations that are not transparent about how their systems gather data telemetry without offering shared data ownership risk product rejection, regu...
The best way to leverage your Cloud Expo presence as a sponsor and exhibitor is to plan your news announcements around our events. The press covering Cloud Expo and @ThingsExpo will have access to these releases and will amplify your news announcements. More than two dozen Cloud companies either set deals at our shows or have announced their mergers and acquisitions at Cloud Expo. Product announcements during our show provide your company with the most reach through our targeted audiences.
SYS-CON Events announced today that Cloud Academy will exhibit at SYS-CON's 20th International Cloud Expo®, which will take place on June 6-8, 2017, at the Javits Center in New York City, NY. Cloud Academy is the industry’s most innovative, vendor-neutral cloud technology training platform. Cloud Academy provides continuous learning solutions for individuals and enterprise teams for Amazon Web Services, Microsoft Azure, Google Cloud Platform, and the most popular cloud computing technologies. Ge...
20th Cloud Expo, taking place June 6-8, 2017, at the Javits Center in New York City, NY, 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 strategy.
Bert Loomis was a visionary. This general session will highlight how Bert Loomis and people like him inspire us to build great things with small inventions. In their general session at 19th Cloud Expo, Harold Hannon, Architect at IBM Bluemix, and Michael O'Neill, Strategic Business Development at Nvidia, discussed the accelerating pace of AI development and how IBM Cloud and NVIDIA are partnering to bring AI capabilities to "every day," on-demand. They also reviewed two "free infrastructure" pr...
Have you ever noticed how some IT people seem to lead successful, rewarding, and satisfying lives and careers, while others struggle? IT author and speaker Don Crawley uncovered the five principles that successful IT people use to build satisfying lives and careers and he shares them in this fast-paced, thought-provoking webinar. You'll learn the importance of striking a balance with technical skills and people skills, challenge your pre-existing ideas about IT customer service, and gain new in...