Accumulative is an interface proposed for the intermediate accumulation type A of Collector<T, A, R> in order to make defining custom Java Collectors easier. Introduction If you’ve ever used Java Streams, you most likely used some Collectors, e.g.: Collectors.toList Collectors.toMap But have you ever used… A composed Collector? It takes […]
Functional Programming
4 posts
Filterer is a pattern that should be applied only in certain cases. In the original post, I presented a very simple example intended to show how to apply it. In this post, I present a much more detailed example that’s intended to also explain when and why to apply it. […]
The Transformer pattern is a design pattern for Java (and potentially other OO languages with use-site variance only and invariant parameter types) that helps objects within a subtype hierarchy fluently transform themselves into objects of any type. Context I was following the OpenJDK threads (Sep 18-21, Nov 12-13, Nov 13-30, […]
Originally published on DZone on June 4, 2018. The Filterer pattern is a design pattern for Java (and potentially other OO languages with use-site variance only) that helps container-like objects return filtered versions of themselves. Disclaimer: What I am writing about here is my own idea, but it is quite likely that […]