I have been writing a program that watches a directory and when files are created in it, it changes the name and moves them to a new directory. In my first implementation I used Java’s Watch Service API which worked fine when I was testing 1kb files. The problem that came up is that in reality the files getting created are anywhere from 50-300mb. When this happened the watcher API would find the file right away but could not move it because it was still being written. I tried putting the watcher in a loop (which generated exceptions until the file could be moved) but this seemed pretty inefficient.
Since that didn’t work, I tried up using a timer that checks the folder every 10s and then moves files when it can. This is the method I ended up going for.
Question: Is there anyway to signal when a file is done being written without doing an exception check or continually comparing the size? I like the idea of using the Watcher API just once for each file instead of continually checking with a timer (and running into exceptions).
All responses are greatly appreciated!
nt
Write another file as an indication that the original file is completed.
I.g ‘fileorg.dat’ is growing if done create a file ‘fileorg.done’ and check
only for the ‘fileorg.done’.
With clever naming conventions you should not have problems.