Is Java 7 WatchService Slow for Anyone Else?

java nio watchservice
sbook picture sbook · Mar 6, 2012 · Viewed 9.9k times · Source

WatchService looks like a great technology but its been too slow to be useful on the OS X and Linux systems I've tested on. To add insult to injury, it doesn't seem to get notified of all events either.

This is the case both with my own code and the canonical example from Oracle. (http://docs.oracle.com/javase/tutorial/displayCode.html?code=http://docs.oracle.com/javase/tutorial/essential/io/examples/WatchDir.java)

I recognize that the OS X OpenJDK port is unsure of this functionality (see https://wikis.oracle.com/display/OpenJDK/Mac+OS+X+Port+Project+Status)

Has anyone been using this in production with success?

Answer

makc picture makc · Aug 21, 2013

I have much better response times if I change

folder.register(watcher, StandardWatchEventKinds.ENTRY_MODIFY);

to

folder.register(watcher, new WatchEvent.Kind[]{StandardWatchEventKinds.ENTRY_MODIFY}, SensitivityWatchEventModifier.HIGH);

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