Keywords or tags summarize documents on an abstract level and can also be used for describing code fragments. They might be leveraged for retrieving features of a software system, understanding program functionality, or providing additional context. While automatic approaches at best are only able to retrieve information that is already contained in the source code, manual tagging could add valuable extra information from qualified expertise of the developers. However, tagging code is tedious. To make code tagging more fun, we introduce a social gamification approach: developers independently tag code fragments and are rewarded if their solutions conform to the solution of other developers. We implemented the game as a Facebook plugin. A pilot user study suggests that the game mechanics are motivating and promote the proposition of reasonable tags.

In this paper we introduce a visual representation of Java objects that can be used for observing and manipulating behavior and state of currently developed classes. It runs separately, e.g., on a tablet, beside an integrated development environment. Within the visualization, developers are able to arbitrarily change the object state, then invoke any method with custom parameters and observe how the object state changes. When changing the source code of the related class, the visualization holds the previous object state and adapts the new behavior defined by the underlying source code. This instantly enables developers to observe functionalities objects of a certain class have and how they manipulate their state, and especially, how source code changes influence their behavior. We implemented a first prototype as a touch-enabled web application that is connected to a conventional integrated development environment. In order to gain first practical insights, we evaluated our approach in a pilot user study.