i'm trying to build a semi file sharing program, when each computer acts both as a server and as a client.

I give multiple threads the option to DL the file from my system.

also, i've got a user interface that can recieve a delete message.

my problem is that i want that the minute a delete message receieved, i wait for all the threads that are DL the file to finish DL, and ONLY than excute file.delete(). what is the best way to do it?

I thought about some database that holds > and iterate and check if the thread is active, but it seems clumsy. is there a better way? thanks