amber-docs VS jmolecules

Record patterns are one step on the path to general pattern matching utility. The bigger building block is general deconstructors. I recommend reading Functional Transformation of Immutable Objects by Brian Goetz. The idea of "withers" shown there requires deconstructors:

https://github.com/openjdk/amber-docs/blob/master/eg-drafts/...

This is the vague plan.

You may be joking but...

Here is the much more detailed version: https://github.com/openjdk/amber-docs/blob/master/eg-drafts/reconstruction-records-and-classes.md

This kind of pattern matching is discussed in the design notes: https://github.com/openjdk/amber-docs/blob/master/site/design-notes/patterns/pattern-match-object-model.md

True, but that only pushes the question of value down the line.

I'm curious about lenses because Java did have a serious problem that required a solution: working with "simple" data correctly was difficult. The chosen solution was ADTs, so we did buy into that. But the approach being explored for transforming records (https://github.com/openjdk/amber-docs/blob/master/eg-drafts/...) only works one level at a time rather than for an entire path. So I wonder how valuable it would be to have a solution for paths. If the answer is that it's mostly valuable for an approach we haven't bought into yet, then we might not need to consider it just yet.

Just a heads up, something like that spread operator is actually coming sooner or later to java: https://github.com/openjdk/amber-docs/blob/master/eg-drafts/...

Pattern matching (for records) is already a preview feature.

Spring Modulith is the successor of Oliver Drotbohm's Moduliths project (with a trailing S). It uses both ArchUnit and jMolecules. At the time of this writing, it's experimental.

You could move towards modeling your code around DDD building blocks (like aggregates etc.) and declare those concepts in code explicitly using jMolecules types. There is a dedicated jMolecules Integrations ByteBuddy Plugin, that would then add the necessary boilerplate code and default mappings required by the expressed concept. This makes the code shown here a fully working JPA model. You can argue that the lack of JPA oddities is odd itself in the first place but I like the idea of expressing the architectural concept explicitly and the technology integration completely flowing from that.