In IncomingFileTransfer.java there is a use of FutureTask on lines 182-193 that is executed incorrectly.
Executing a FutureTask in this style does not run the FutureTask asynchronously. To run a FutureTask asynchronously a Thread must be created or the task must be executed via an ExecutorService.
A simple fix would be to replace
190: streamNegotiatorTask.run();
with
190: new Thread(streamNegotiatorTask).start();
In IncomingFileTransfer.java there is a use of FutureTask on lines 182-193 that is executed incorrectly.
Executing a FutureTask in this style does not run the FutureTask asynchronously. To run a FutureTask asynchronously a Thread must be created or the task must be executed via an ExecutorService.
A simple fix would be to replace
190: streamNegotiatorTask.run();with
190: new Thread(streamNegotiatorTask).start();