Depends on how flexible you want to be. You
could use the java.io.File class to walk the directory structure of the disk looking for the file, but I don't recommend that
Instead, I just put my properties in classpath and don't worry about the directory. Loading the Properties through PropertyResourceBundle.getBundle("myPropertiesFile") uses the classpath, so as long as my file is in the classpath I don't worry about it. If I don't have a resource in the classpath, I don't have the resource.
(Of course, I'm looking at moving to Preferences anyway...)
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