About Question enthuware.ocpjp.v7.2.1554 :

[Chen@ukr.net]

PosixFileAttributeView

Unix based file systems provide this view. This view supports the following attributes in addition to BasicFileAttributeView:

"permissions" : Set<PosixFilePermission>
"group" : GroupPrincipal

The permissions attribute is used to update the permissions, owner, or group-owner as by invoking the setPermissions, setOwner, and setGroup methods respectively.

https://docs.oracle.com/javase/7/docs/a ... eView.html

there is no setOwner method

Only method for updates the file group-owner - void setGroup(GroupPrincipal group)

[admin]

It inherits the setOwner method from FileOwnerAttributeView. It is listed in the link you mentioned above.

[Chen@ukr.net]

thanks.