虚拟文件系统映射到本地文件

Question

How can I decorate some remote filesystem like a path to directory in java? For example something like this:

File decoratorFileSystem = new File("ftp://host/path"); // this does not work of course
...
File file1 = new File(decoratorFileSystem, "somefile1");
File file2 = new File(decoratorFileSystem, "somefile2");

So when I will use file1 , file2 or others decorated files I get access to remote file from the decorated filesystem as if it local file with corresponded restrictions.

I think to use virtual file system from "org.apache.commons.vfs2.provider...." but I am not sure is this right way...

Answer 1

A File in Java can only ever reference a real file on a filesystem mounted by the OS (ie something that the OS knows to be a file).

Virtual filesystems can't be accessed this way (unless it's handled by the OS, ie if you mount a FTP directory directly under Linux, you can use a File ).

The newer Path class from NIO2 (available in Java 7 and later) however was explicitly designed with virtual file systems in mind.

Look at this tutorial and the FileSystemProvider class to find out how to define your own virtual file system. The Zip File System Provider is a sample implementation.