Notes on the Java class loading process including loading, verification, preparation, resolution, initialization, usage, and unloading.

A concise overview of Java thread states with transitions and practical notes.

Key parameters and behaviors of Java thread pools, including sizing strategy, queues, factories, and rejection policies.

Quick notes on JVM memory generations, GC survivor spaces, metaspace, and common tuning flags.

Concise notes on the full Spring Bean lifecycle including instantiation, dependency injection, initialization hooks, BeanPostProcessor phases, usage, and destruction.