What is a HashSet A HashSet is an unordered collection containing unique elements. It has the standard collection operations Add, Remove, Contains, but since it uses a hash-based implementation, these operations are O(1) Learn with a Programming Question ... (more…)

A pragmatic guide to Java logging—what should we log, what shouldn’t we log, and how to implement Java logging properly. (more…)

I have made various contributions to the RoaringBitmap Java library since early 2017, often creating performance improvements. Sometimes these performance improvements are completely transparent and just kick in when users update version, but some of them... (more…)

Many developers were burned by the overly complex world of Java back in the early 2000s. The Gang of Four patterns and middleware / J2EE / Java EE led to ridiculous levels of alleged decoupling as is evident in this sequence diagram from an open source J... (more…)

Philippe Back's answer: One would learn Smalltalk before Java so that one will be aware that there are other ways than factories, helpers, proxies, and such Java often used “idioms.”... (more…)