  The Android framework provides a rich set of APIs that can be exploited by
developers to build their apps. However, the rapid evolution of these APIs
jointly with the specific characteristics of the lifecycle of the Android
components challenge developers, who may release apps that use APIs
incorrectly. In this demo, we present Proactive Libraries, a tool that can be
used to decorate regular libraries with the capability of proactively detecting
and healing API misuses at runtime. Proactive Libraries blend libraries with
multiple proactive modules that collect data, check the compliance of API
usages with correctness policies, and heal executions as soon as the possible
violation of a policy is detected. The results of our evaluation with 27
possible API misuses show the effectiveness of Proactive Libraries in
correcting API misuses with negligible runtime overhead.
