Are Variable, Array, and Object Diagrams in Introductory Java Textbooks Explanative?

Diagrams in textbooks are essential tools in explaining concepts. An effective diagram helps a novice learner build a runnable mental model, increase recall and improve problem-solving skills. Richard Mayer suggests that for a diagram to be effective, it must be explanative and, thus, document two major features: system topology and component behaviour. We surveyed diagrams of variables, arrays and objects in 15 commonly used introductory Java textbooks to investigate if the diagrams are explanative. This abstract presents the analysis of arrays.