问题
The Path class has no documented constructor, but one creates instances via. Paths.get( "...." ) which is a shorthand for FileSystems.getDefault().getPath( "..." ). So can someone explain this design decission?
回答1:
can someone explain this design decision?
It is because JSR 203 allows paths to be issued from more than one FileSystem, unlike File, which is always linked to the file system the JVM lives on. In JSR 203, this filesystem is called the default filesystem. You can get a reference to it using FileSystems.getDefault().
You use Paths.get() to get a path from the default filesystem, which is strictly equivalent to FileSystems.getDefault().getPath(). If you were to get a Path from another file system, you would use this particular file system's .getPath().
As a proof that a FileSystem can be for (nearly) anything, here are a few implementations over different sources:
- in memory;
- FTP;
- SMB/CIFS;
- Dropbox.
And there are a few others.
来源：https://stackoverflow.com/questions/28040971/why-there-is-no-path-constructor-in-java-nio-files-path