Class Permissions
- All Implemented Interfaces:
Serializable
Permission
objects,
organized into PermissionCollection
objects. For example, if any
java.io.FilePermission
objects are added to an instance of
this class, they are all stored in a single PermissionCollection
.
It is the PermissionCollection
returned by a call to
the newPermissionCollection
method in the FilePermission
class. Similarly, any java.lang.RuntimePermission
objects are
stored in the PermissionCollection
returned by a call to the
newPermissionCollection
method in the RuntimePermission
class. Thus, this class represents a collection of
PermissionCollection
objects.
When the add
method is called to add a Permission
, the
Permission
is stored in the appropriate PermissionCollection
.
If no such collection exists yet, the Permission
object's class is
determined and the newPermissionCollection
method is called on that
class to create the PermissionCollection
and add it to the
Permissions
object. If newPermissionCollection
returns
null
, then a default PermissionCollection
that uses a
hashtable will be created and used. Each hashtable entry stores a
Permission
object as both the key and the value.
Enumerations returned via the elements
method are
not fail-fast. Modifications to a collection should not be
performed while enumerating over that collection.
- Since:
- 1.2
- See Also:
-
Constructor Summary
ConstructorDescriptionCreates a newPermissions
object containing noPermissionCollection
objects. -
Method Summary
Modifier and TypeMethodDescriptionvoid
add
(Permission permission) Adds aPermission
object to thePermissionCollection
for the class the permission belongs to.elements()
Returns an enumeration of all thePermission
objects in all thePermissionCollection
objects in thisPermissions
object.boolean
implies
(Permission permission) Checks to see if this object'sPermissionCollection
for permissions of the specified permission's class implies the permissions expressed in the permission object.Methods declared in class java.security.PermissionCollection
elementsAsStream, isReadOnly, setReadOnly, toString
-
Constructor Details
-
Permissions
public Permissions()Creates a newPermissions
object containing noPermissionCollection
objects.
-
-
Method Details
-
add
Adds aPermission
object to thePermissionCollection
for the class the permission belongs to. For example, if permission is aFilePermission
, it is added to theFilePermissionCollection
stored in thisPermissions
object. This method creates a newPermissionCollection
object (and adds the permission to it) if an appropriate collection does not yet exist.- Specified by:
add
in classPermissionCollection
- Parameters:
permission
- thePermission
object to add.- Throws:
SecurityException
- if thisPermissions
object is marked as readonly.- See Also:
-
implies
Checks to see if this object'sPermissionCollection
for permissions of the specified permission's class implies the permissions expressed in the permission object. Returnstrue
if the combination of permissions in the appropriatePermissionCollection
(e.g., aFilePermissionCollection
for aFilePermission
) together imply the specified permission.For example, suppose there is a
FilePermissionCollection
in thisPermissions
object, and it contains oneFilePermission
that specifies "read" access for all files in all subdirectories of the "/tmp" directory, and anotherFilePermission
that specifies "write" access for all files in the "/tmp/scratch/foo" directory. Then if theimplies
method is called with a permission specifying both "read" and "write" access to files in the "/tmp/scratch/foo" directory,true
is returned.Additionally, if this
PermissionCollection
contains theAllPermission
, this method will always returntrue
.- Specified by:
implies
in classPermissionCollection
- Parameters:
permission
- thePermission
object to check.- Returns:
true
if "permission" is implied by the permissions in thePermissionCollection
it belongs to,false
if not.
-
elements
Returns an enumeration of all thePermission
objects in all thePermissionCollection
objects in thisPermissions
object.- Specified by:
elements
in classPermissionCollection
- Returns:
- an enumeration of all the
Permission
objects. - See Also:
-