如何使用超时机制中断正在进行的任务？

I'm currently developping a ftp client based on the package commons.net, in order to run tests to see the speed of the connection. Basically my ftp test consists in connect to the server, logging onto it, and then start a cycle of download/upload as long as necessary, until the user decides to stop it via a button, then the current cycle will end and so will the test.I'm currently developping a ftp client based on