What are those ._ files? I downloaded a Java library and noticed, that for every file and directory there is a binary file of the form ._&lt;name&gt;. It contains something like:


  "Mac OS X ... com.apple.quarantine ... com.google.Chrome"


Have those files been added by an Mac OS X IDE (I'm an Ubuntu user planning to use the library with Eclipse)? Can I safely remove those files?

TIA for your help!
Those are extended attribute files, which OSX uses when the filesystem doesn't support resource forks or extended attributes.  You don't care about them.  (The entry you quoted is a message to the Finder to display a "This file was downloaded at (date).  Downloaded programs may be unsafe.  Do you want to open it?" dialog along with a button which will open Chrome and take you to the page the file was downloaded from.)