mike.mainguy

The most important factor that contributes to a successful software project is ensuring that the development staff has a good understanding of the requirements. Incorrect requirements almost guarantee incorrect software behavior. Most often, however, the requirements aren't clearly incorrect, but rather they are vague, ambiguous, or make incorrect assumptions about the best way to apply technology to solve the problem. The original title of this post was "Writing Good Software Requirements", but I realized after writing the previous paragraph (irony noted) that writing good requirements is actually part of the problem. Having written software my entire adult life and much of my childhood, I've been most effective writing software for myself. This software has always done exactly what it was supposed to do (technical bugs notwithstanding) and the reason is because I had a visceral and complete understanding of the problem I was trying to solve and what factors...

In java, writing equals and hashcode methods are perennial problems. Newbies and experts alike are confounded when things go haywire and troubleshooting problems can be extremely difficult. A common thing that a poor hashcode/equals implementation will cause are intermittent problems and/or mysterious out of memory errors. To help clear things up, I'll give a 10,000 overview of how the core java libraries use the hashcode/equals methods. Essentially, the hashcode/equals methods are used when storing things in Hashes (HashMap, Hashtable, HashSet). Things often go wrong when folks start using custom objects as keys for these classes. For example, let's say we have a person class that looks something like this: public class Person { public Person(String orgName) { this.name = orgName } private String name; public String getName() { ...