As another comment has written one needs Runtime.getRuntime().addShutdownHook(). The hook then, for example, closes the input stream to ensure that it’s reader

As another comment has written one needs Runtime.getRuntime().addShutdownHook(). The hook then, for example, closes the input stream to ensure that it’s reader is woken up from a blocking read and then waits until the already read data is written. In turn this requires to know how synchronization works.