Returns a new PermissionCollection object for storing FilePermission objects.
FilePermission objects must be stored in a manner that allows them to be inserted into the collection in any order, but that also enables the PermissionCollection implies
method to be implemented in an efficient (and consistent) manner.
For example, if you have two FilePermissions:
-
"/tmp/-", "read"
-
"/tmp/scratch/foo", "write"
and you are calling the implies
method with the FilePermission:
"/tmp/scratch/foo", "read,write",
then the
implies
function must take into account both the "/tmp/-" and "/tmp/scratch/foo" permissions, so the effective permission is "read,write", and
implies
returns true. The "implies" semantics for FilePermissions are handled properly by the PermissionCollection object returned by this
newPermissionCollection
method.
@return a new PermissionCollection object suitable for storing FilePermissions.