Also known as Pseudo-Analysis and Blind Development, Mushroom Management is often described by this phrase: "Keep your developers in the dark and feed them fertilizer." An experienced system architect recently stated, "Never let software developers talk to end users." Furthermore, without end-user participation, "The risk is that you end up building the wrong system." AntiPattern Problem In some architecture and management circles, there is an explicit policy to isolate system developers from the...

Background Cut-and-Paste Programming is a very common, but degenerate form of software reuse which creates maintenance nightmares. It comes from the notion that it's easier to modify existing software than program from scratch. This is usually true and represents good software instincts. However, the technique can be easily over used. General Form This AntiPattern is identified by the presence of several similar segments of code interspersed throughout the software project. Usually, the project...

AntiPattern Problem Using today's software technology is analogous to walking through a high-technology mine field. This mini-AntiPattern is also known as Nothing Works or Do You Believe in Magic? Numerous bugs occur in released software products; in fact, experts estimate that original source code contains two to five bugs per line of code. This means that the code will require two or more changes per line to remove all defects. Without question,...

AntiPattern Problem Software that fails straightforward behavioral tests may be an example of an Input Kludge, which occurs when ad hoc algorithms are employed for handling program input. For example, if the program accepts free text input from the user, an ad hoc algorithm will mishandle many combinations of legal and illegal input strings. The anecdotal evidence for an Input Kludge goes like this: "End users can break new programs within moments...

Background The Spaghetti Code AntiPattern is the classic and most famous AntiPattern; it has existed in one form or another since the invention of programming languages. Nonobject-oriented languages appear to be more susceptible to this AntiPattern, but it is fairly common among developers who have yet to fully master the advanced concepts underlying object orientation. General Form Spaghetti Code appears as a program or system that contains very little software structure. Coding and...

AntiPattern Problem A Dead End is reached by modifying a reusable component, if the modified component is no longer maintained and supported by the supplier. When these modifications are made, the support burden transfers to the application system developers and maintainers. Improvements in the reusable component cannot be easily integrated, and support problems may be blamed on the modification. The supplier may be a commercial vendor, in which case this AntiPattern is...

Background This is one of the most common AntiPatterns in the industry. Frequently, a vendor, specifically a database vendor, will advocate using its growing product suite as a solution to most of the needs of an organization. Given the initial expense of adopting a specific database solution, such a vendor often provides extensions to the technology that are proven to work well with its deployed products at greatly reduced prices. General Form A...

AntiPattern Problem A Boat Anchor is a piece of software or hardware that serves no useful purpose on the current project. Often, the Boat Anchor is a costly acquisition, which makes the purchase even more ironic. The reasons for acquiring a Boat Anchor are usually compelling at the time. For example, a policy or programmatic relationship may require the purchase and usage of a particular piece of hardware or software. This is...

Background When Michael Akroyd presented the Gypsy AntiPattern at Object World West in 1996, he likened the transient appearance and then discrete vanishing of the gypsy class to a "Gypsy Wagon" that is there one day and gone the next. As we studied Akroyd's model, we wanted to convey more of the Gypsy's invoking function in the overall AntiPattern name. Thus, we felt that since poltergeists represent "restless ghosts" that cause "bump-in-the-night...

Background Functional Decomposition is good in a procedural programming environment. It's even useful for understanding the modular nature of a larger-scale application. Unfortunately, it doesn't translate directly into a class hierarchy, and this is where the problem begins. In defining this AntiPattern, the authors started with Michael Akroyd's original thoughts on this topic. We have reformatted it to fit in with our template, and extended it somewhat with explanations and diagrams. General Form This...