Prerequisite Review: Java Object, WPILib Subsystem, ROS 2 Node

This route no longer teaches classes, constructors, encapsulation, or this from scratch. Those belong in java-programming.

The bridge-specific question is architectural:

When do three things that all look like "components" actually belong to different runtime models?

Compare:

• a plain Java object, which owns local JVM state and methods;
• a WPILib subsystem, which participates in a Java robotics framework and scheduler model;
• a ROS 2 node, which participates in the ROS graph and middleware communication model.

Shared vocabulary such as "component," "state," or "responsibility" does not make these equivalent runtime entities.

Required artifact

Produce a Component Boundary Card with one example of each model, what runtime owns it, what evidence can prove its existence/behavior, and one invalid cross-layer claim to reject.

If object-oriented Java mechanics require review, return to java-programming. This bridge keeps the architecture comparison and removes duplicated OOP instruction.