This post is the first public step in the series built from the custom-ioc-container project.
The goal is not to recreate Spring, but to isolate a few core mechanisms inside a deliberately small scope: runtime annotations, constructor selection, reflection-based instantiation, singleton caching, and dependency graph validation.
Why start from a tiny container
Frameworks become much easier to understand once you have rebuilt a minimal version of their underlying ideas.
By building a plain Java IoC container, I can explain:
- what annotations actually contribute at runtime
- how an object graph can be resolved without magic
- where the design choices start to make a framework either useful or brittle
What the full article will cover
The long version will come with code, annotated excerpts, and a few diagrams.
It will cover at least:
- the annotations used by the container
- recursive dependency creation
- singleton lifecycle management
- configuration error detection
- the limits of this approach compared to a mature framework
Editorial direction
The intent is to stay concrete: start from code, show the tradeoffs, and only then move back up to the architectural concepts.
So this page is still transitional, but it already defines the topic and the direction of the series.