There is a problem when the "integration tests" are attempting to stop flume on Windows using Process.destroy(). This does a brute force kill of the top level shell (running the startup script) which then leaves a child java process (i.e flume agent) running.
The brute force kill does not allow the shell to terminate the child java process. Maven somehow notices that child processes are running and waits indefinitely for them to terminate... causing a hang.
Suggestion is to implement a shutdown command support using JMX. This gives the integration tests a graceful mechanism to terminate flume. Also in production use cases this mechanism can be secured with authentication etc.