APCSjava.com - Java code visualizations for AP Computer Science A

This website (made by the creator of Python Tutor) helps teachers and students work with the new AP Computer Science A Course and Exam Description launched in 2025. This revised curriculum pushes more of the AP exam toward reading unfamiliar code and working out what it does as it runs, which is the exact skill that our step-by-step Java code visualizer helps students to build.


The full website is still under construction. In the meantime here are two resources you can use today!

1) Mrs. Littman’s AP CS Java visualizer examples

Sue Littman teaches AP Computer Science A at TVT Community Day School in Irvine, California. She created a free collection of interactive Java examples that follow the new AP curriculum.

Browse Mrs. Littman’s AP CS A resources →

2) How the Java visualizer helps your AP CS class

Philip Guo, creator of Python Tutor, wrote a guide for AP Computer Science A teachers that walks through all four units of the new 2025 AP standards and shows what the Java visualizer can illustrate in each.

Read the full article →

The article contains many code visualization examples, such as this one building an ArrayList of song titles. Drag the slider back to the beginning and step forward: