Physical Java — 3. Written Objects

Physical Java is a sequence consisting of the following 6 notional machines:
1. Arrays & Refs
2. Physical Objects
3. Written Objects
4. Refs as Arrows
5. Paper List/ListNode
6. Inheritance

Programming Language

imperative / Java

Form

Representation

Attribution — Origin / Source

Collected by Colleen Lewis — Own practice

Conceptual Advantage

Helps students plan code; avoids confusion of crossed out arrows.

Mapping

PLNM
... (all aspects of Physical Java 1)
object object type written/underlined in a rectangle
int number written in a small box
instance variables shown in an object

Draws Attention To

The effect of resetting references.

Use When

When having students implement a LinkedList in Java.

Cost

Creating the physical model is a lot of work.

Comments or Feedback?

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