Lightweight Java Visualizer – LJV
A short introduction for AP Computer Science* teachers
LJV has many uses for the AP Computer Science teacher.
LJV can help students to visualize relationships
A Triangle object containing LineSegments each containing Point objects.
LJV is so EASY to use! Click on any image to see the source code that created it.
Just as easily LJV can help students to better understand arrays.
An array with four numbers.
A five element array with 3 references to Point objects.
Same five element array with a
different look (requires two extra lines of code.)
LJV can take some of the mystery out of Java collections classes.
An ArrayList with references to 5 Point objects.
Students can experiment – what happens to this ArrayList after an 11th Point is added? LJV calls can be inserted at several points in a program, creating a sequence of images that can show insertions, deletions, etc.
Imagine drawing the following HashMap example on the board!
Students can use LJV to see their own data structures – implementations of Queue, Stacks, and PriorityQueues, as well as structures using TreeNodes and ListNodes.
Source code: Point.java and LineSegment.java
Let's get started!
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