Java: Path vs File
Long story short:
java.io.File will most likely never be deprecated / unsupported. That said, java.nio.file.Path is part of the more modern java.nio.file lib, and does everything java.io.File can, but generally in a better way, and more.
For new projects, use Path.
And if you ever need a File object for legacy, just call Path#toFile()
Migrating from File to Path
Article by Janice J. Heiss and Sharon Zakhour, May 2009, discussing NIO.2 File System in JDK 7
Check this article about more info - http://www.oracle.com/technetwork/articles/javase/nio-139333.html
Basically file.Path will be the way to go from now on but as is widely known Java people tend to keep back-compatibility so I guess that's why they have left it.