Object-oriented programming supports object mu- tation during a program
execution. A mutation occurs whenever a value is assigned to an object field.
Analyzing the evolution of object mutation is known to be difficult.
Unfortunately, classical code debuggers painfully support the analysis of
object mutations. Object Evolution Blueprint is a visualization dedicated to
exploring object mutation over time. Our blueprint visually and concisely
represents sequences of field mutations. The history of each field is
adequately shown with respect to the dynamic value types. We have observed the
use of our blueprint with three practitioners. Our visualization has been well
received and accepted to complete two different software comprehension tasks.
Moreover, our user study shows that the visualization is both intuitive and
simple to learn.