Monday, June 23, 2014

I Don't Think That Software Development Word Means What You Think It Means

There are several terms used inappropriately or incorrectly in software development. In this post, I look at some of these terms and the negative consequences of misuse of these terms.

"agile"

The Agile Manifesto started a movement that resonated with many software developers frustrated with inefficiencies and inadequacies of prevalent software development methodologies. Unfortunately, the relatively simple concepts of the Agile Manifesto were interpreted, changed, evangelized, commercialized, and sold in so many different ways that it became difficult to uniquely describe agile. To some, agile became synonymous with "no documentation" and to others agile meant going straight to coding without any process. So many disparate methodologies and practices are now sold as agile that it's become increasingly difficult to describe what makes something agile or not.

There have been several negative consequences of the multiple interpretations of what agile means. Implementation of so-called agile practices without understanding of agile can lead to failures that are blamed on agile, but which failures may have little or nothing to do with agile. Unrealistic expectations of agile and what it can do for development can lead to inevitable disappointment as there still is no silver bullet. It is difficult to help new developers, developers new to agile, managers, customers, and other stakeholders understand what agile is and how it may or may not be appropriate for them with so many different interpretations. I was at a presentation by an agile enthusiastic several years ago when he suggested that agile was anything that was successful and was not anything that is not successful.

For me, "agile" means processes and approaches that closely match the values outlined in the Agile Manifesto (individuals and interactions, working software, customer collaboration, and responding to change). There are other approaches and methodologies out there that may be useful and positive, but if they aren't inspired by these values, it is difficult for me to hear them called "agile."

"REST"

Roy Fielding's dissertation Architectural Styles and the Design of Network-based Software Architectures popularized the term Representational State Transfer (REST). Unfortunately, many have used REST and HTTP interchangeably and in the process have muddled the conversations about both the REST architectural style and the Hypertext Transfer Protocol (HTTP).

It is easy to see from a historical perspective why REST and HTTP are often treated interchangeably. REST embraced the functionality already provided by HTTP as a significant part of its architectural style at a time other popular architectural styles and frameworks were doing everything they could to hide or abstract away HTTP specifics details. REST leverages HTTP's stateless nature while others were trying to wrap HTTP with state. Although REST certainly played a major role in raising awareness of HTTP, REST is more than HTTP. I have found that many who think of REST and HTTP as one and the same don't appreciate the HATEOAS concept in REST. HATEOAS stands for Hypermedia as the Engine of Application State and refers to the concept of application state being embodied within the hypermedia exchanged between server and client rather than in the client.

"refactoring"

I've known of clients and managers filled with dread when they hear a developer state that he or she is going to "refactor" something. The reason is that "refactoring" too often means the developer plans to change the code structure and "improve" or "fix" behavior as part of this. Refactoring is supposed to be code improvements that do not effect the results of the software but lead to more maintainable code. Too many developers are lured into making other changes "while they are in the code" that change results. Even when for the better, these changes are not in the spirit of refactoring and so, when they have led to breaking of existing functionality, have led to "refactoring" being seen in a bad light.

Comprehensive unit tests and other tests can help ensure that refactoring does not change any expected behavior, but developers should also clearly understand whether the goal is to maintain current functionality with improved code structure (refactor) or actually change/improve functionality and only use the term "refactoring" when appropriate to avoid confusion.

"premature optimization"

I generally agree with the principle behind the now famous quotation, "Premature optimization is the root of all evil." However, my interpretation of this is that one should not write less maintainable or less readable code in an attempt to achieve small expected performance gains. However, as I posted in When Premature Optimization Isn't, this term occasionally gets used as justification for not making good architecture and high-level design decisions just because they have a performance benefit associated with them. Some architectural decisions are difficult to change at a later point and performance does need to be accounted for. Similarly, even at implementation level, there are times when better performing code is as readable and easy to write as less performing code and so there is no good reason to not write the better performing code.

NoSQL

The term NoSQL was an unfortunate one for a class of databases that probably would have been better labeled "Not Relational." As numerous "NoSQL databases" have adopted SQL (without adopting the relational model), alternative terms have been tried such as "Not Just SQL."

"open source"

The term "open source" has often led to confusion about whether the software in question is "free" in terms of "freedom" (libre/free speech) and/or "free" in terms of no monetary price (gratuit/free beer). There can even be confusion about the minor differences between "open source" and "free software." For me, "open source" means source code that I can look at and modify as necessary.

JavaScript

With JavaScript's increased popularity, its poorly chosen name does not seem to confuse as many people as it used to. However, I still do occasionally hear people who think that JavaScript must have some relationship to Java because "Java" is in both languages' names.

SLOC

I generally despise everything about the idea of source line of code. The appeal of SLOC is the pretense that somehow lines of code can be counted the same as beans and widgets. All lines of code are not created equal and there are differences in lines of code across different languages, across different developers, and across different functionality. Some have even gone so far as to think that more SLOC is always a good thing whereas I've found that more concise code with fewer lines of code can often be preferable. I have blogged before on lines of code and unintended consequences.

SOAP

This one is not a big deal in terms of negative consequences from its misuse, but it is worth noting that SOAP no longer stands for Simple Object Access Protocol.

JDBC

This is another one that doesn't really lead to any problems even though it technically has never stood for Java Database Connectivity and is not even an acronym. The fact that it does indeed relate to connecting to databases, that it is Java-related, and that it is so widely said to stand for Java Database Connectivity means that this misuse of the term JDBC has no significant negative side effects. In fact, I suspect that Sun Microsystems folks intentionally wanted people to think of it as an acronym for Java Database Connectivity while explicitly stating that it was not an acronym because it allowed people to quickly understand what JDBC is via their awareness of ODBC.

Conclusion

The incorrect use of many of the terms discussed in this post could be described as largely pedantic, but misuse of a few of them can lead to miscommunication and general confusion. In some cases (such as "agile" and "refactoring"), the misuse of terms has led to negative experiences and soiled reputations for those terms. In other cases (such as using JDBC and SOAP as acronyms when they really are not acronyms), the confusion seems small and harmless as everyone discussing the falsely advertised "acronym" seems to understand what it implies.

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