This post is intended as support material for another post of mine; see Towards Authoritative Software Design.

The Universal Modeling Language (UML) (Wikipedia) was intended to be a standard notation for expressing software designs, and to replace the multitude of ad-hoc notations that software architects have been using on various mediums such as whiteboard, paper, and general-purpose box-and-arrow diagram-drawing software. The idea was that by following a standard notation which prescribes a specific way of expressing each concept, every diagram would be readily and unambiguously understood by everyone.

It has miserably failed.

The origins of the debate go so far back that they are lost in the mists of time, but a good starting point (which contains references to prior debate) is an Internet Draft from 2018 titled Terminology, Power, and Inclusive Language in Internet-Drafts and RFCs. Some especially woke communities like the Python community had already started applying some of the recommendations in this draft as early as 2019, but things really picked up steam in 2020, with the murder of George Floyd.

I knew I was definitely going to watch this one, from just the title. It turns out that he comes across a bit annoying due to attitude; nonetheless, the talk is definitely worth watching.

Interestingly enough, in his code snippets he is using JavaScript, whereas one of my personal guiding principles is thou shalt not suffer an error to go undetected, which means that no scripting language should be used under any circumstances, for anything at all, by anyone, anywhere, ever. But I digress. Excellent presentation.

![[media/bathyscaphe-logo.svg]]

Abstract

This article introduces Bathyscaphe, an open-source java library that you can use to assert that your objects are immutable and/or thread-safe.

The problem

Programmers all over the world are embracing immutability more and more; however, mutation is still a thing, and in all likelihood will continue being a thing for as long as there will be programmers. In a world where both mutable and immutable objects exist side by side, there is often a need to ascertain that an object is of the immutable variety before proceeding to use it for certain purposes. For example, when an object is used as a key in a hash map, it better be immutable, or else the hash code of the key may change, causing the map to severely malfunction.

Furthermore, when an object is not immutable, there is often the need to ascertain that it is at least thread-safe before sharing it between threads, otherwise there will be race conditions, with catastrophic results.

Note that when any of the above goes wrong, it tends to be a bug which is very difficult to troubleshoot.

Quite often, when I rename a maven module, IntellijIdea gets confused and keeps showing the old module name in the project view.

• Re-importing maven projects does not help.
• Clearing the IntellijIdea caches and restarting does not help.
• Even deleting the .idea directory does not help.

I discovered that this is happening because:

• IntellijIdea keeps information about a project outside of the .idea directory
• IntellijIdea fails to delete that information when you invalidate caches and restart.

The solution I have found to this problem is: