Steps to reproduce (use attached Maven project):
1. Start your remote flume agent
2. Run the Maven project and attach to it with the debugger in your favourite IDE (I use NetBeans)
3. Kill your remote flume agent
4. Rapidly press enter
Each time you press Enter, 2 new threads show up. See the attached screenshot. Notice the panel on the left is littered with new threads. I was pressing Enter rapidly for 30 seconds.
NOTE: This also happens if the remote flume agent hasn't been started at all.