Java, taken apart.

Learn each unit with in-depth visuals and explanations

AP Computer Science A

4 chapters

Using objects and methods

variables, methods and strings

Five lines of Java beside four paper memory boxes: int score holds 42 and int copy holds 7, while the boxes for String name and String other each send a red arrow to the same String object “Ada”

Selection and iteration

if, while and for

A flowchart of paper boxes and decision diamonds, with a red token running the loop that halves n or triples it and adds 1, beside its Java code with the running line lit red and memory cells for n and steps

Class creation

blueprints and the objects they make

A class Player written as Java code on a pale blueprint board stamps out three Player objects, each a paper slab holding its own score and lives in memory cells, with reference variables p1, p2 and p3 whose arrows point to them

Data collections

arrays, lists, searching and sorting

An eight-slot paper array with its indices beneath, mid insertion sort: the key 2 lifted in red above the hole it left at index 1, the sorted part in blue to its left