Procedures

Thank you for participating in this study.

Goal

The goal of this study is compare two tools for adding type qualifiers to existing code.

Anonymity in Screencasts

The researchers video capture the computer screen during the lab study and plan to release the captured videos as a part of the data set of this study. Please avoid actions that would make the videos reveal your identity, e.g., logging into web sites or entering your name inside the source code.

The Nullness Checker Tutorial

Please feel free skim over [the tutorial on the Nullness Checker](Nullness Checker Tutorial), which you've read before, just to refresh your memory.

Annotation Tasks

1. The researcher will ask you to watch the video tutorial of one of the tools and point you to the written version of the tutorial so that, if needed, you can refer back to it later during the study.
2. Please tell the researcher your answers to the questions at the end of the written version of the tutorials.
3. After you finish the tutorial, the researcher will open a project for you to annotate using the tool.
4. Please resolve as many nullness errors/warnings as you can.
5. Please make sure that your uses of the annotations are well justified. For example,
   1. Avoid using @SuppressWarnings annotations and assert statements where you believe they are inappropriate or not needed.
   2. Avoid @Nullable annotations where @NonNull is appropriate and vice versa.
   3. Avoid @NonNull annotations where no annotation is needed.
6. Please feel free to refactor the code, add, remove, or change annotations to make your uses of the annotations well justified. However, please make sure that your changes don't alter the correct observable behavior of the program. In addition, if you see any comments in the source code that begin with TO PARTICIPANTS, please follow their instructions. The code comments that begin with string TO PARTICIPANTS mark parts of the code that you must not change.
7. The Eclipse project is checked in a git repository. Please feel free to open a Linux terminal and use git to review your changes if needed. To find the location of the git repository, right-click on the project in Eclipse and select Properties. The Resource page of the Properties window will show the location of the project on the file system.
8. When you finish annotating the source code, please inform the researcher. The researcher will point you to some instructions so that you verify your annotations.
9. When you finish verifying the annotations, please inform the researcher. The researcher will ask you to repeat the above steps with another tool and project.