- java.lang.Object
-
- java.security.PermissionCollection
-
- java.security.Permissions
-
- All Implemented Interfaces:
- Serializable
public final class Permissions extends PermissionCollection implements Serializable
This class represents a heterogeneous collection of Permissions. That is, it contains different types of Permission objects, organized into PermissionCollections. For example, if anyjava.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 thenewPermissionCollection
method in the FilePermission class. Similarly, anyjava.lang.RuntimePermission
objects are stored in the PermissionCollection returned by a call to thenewPermissionCollection
method in the RuntimePermission class. Thus, this class represents a collection of PermissionCollections.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 thenewPermissionCollection
method is called on that class to create the PermissionCollection and add it to the Permissions object. IfnewPermissionCollection
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.- See Also:
Permission
,PermissionCollection
,AllPermission
-
-
Constructor Summary
Constructors Constructor and Description Permissions()
Creates a new Permissions object containing no PermissionCollections.
-
Method Summary
Methods Modifier and Type Method and Description void
add(Permission permission)
Adds a permission object to the PermissionCollection for the class the permission belongs to.Enumeration<Permission>
elements()
Returns an enumeration of all the Permission objects in all the PermissionCollections in this Permissions object.boolean
implies(Permission permission)
Checks to see if this object's PermissionCollection for permissions of the specified permission's class implies the permissions expressed in the permission object.-
Methods inherited from class java.security.PermissionCollection
isReadOnly, setReadOnly, toString
-
-
-
-
Constructor Detail
-
Permissions
public Permissions()
Creates a new Permissions object containing no PermissionCollections.
-
-
Method Detail
-
add
public void add(Permission permission)
Adds a permission object to the PermissionCollection for the class the permission belongs to. For example, if permission is a FilePermission, it is added to the FilePermissionCollection stored in this Permissions object. This method creates a new PermissionCollection object (and adds the permission to it) if an appropriate collection does not yet exist.- Specified by:
add
in classPermissionCollection
- Parameters:
permission
- the Permission object to add.- Throws:
SecurityException
- if this Permissions object is marked as readonly.- See Also:
PermissionCollection.isReadOnly()
-
implies
public boolean implies(Permission permission)
Checks to see if this object's PermissionCollection for permissions of the specified permission's class implies the permissions expressed in the permission object. Returns true if the combination of permissions in the appropriate PermissionCollection (e.g., a FilePermissionCollection for a FilePermission) together imply the specified permission.For example, suppose there is a FilePermissionCollection in this Permissions object, and it contains one FilePermission that specifies "read" access for all files in all subdirectories of the "/tmp" directory, and another FilePermission that specifies "write" access for all files in the "/tmp/scratch/foo" directory. Then if the
implies
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 the AllPermission, this method will always return true.
- Specified by:
implies
in classPermissionCollection
- Parameters:
permission
- the Permission object to check.- Returns:
- true if "permission" is implied by the permissions in the PermissionCollection it belongs to, false if not.
-
elements
public Enumeration<Permission> elements()
Returns an enumeration of all the Permission objects in all the PermissionCollections in this Permissions object.- Specified by:
elements
in classPermissionCollection
- Returns:
- an enumeration of all the Permissions.
-
-
Document created the 11/06/2005, last modified the 04/03/2020
Source of the printed document:https://www.gaudry.be/en/java-api-rf-java/security/permissions.html
The infobrol is a personal site whose content is my sole responsibility. The text is available under CreativeCommons license (BY-NC-SA). More info on the terms of use and the author.
References
These references and links indicate documents consulted during the writing of this page, or which may provide additional information, but the authors of these sources can not be held responsible for the content of this page.
The author This site is solely responsible for the way in which the various concepts, and the freedoms that are taken with the reference works, are presented here. Remember that you must cross multiple source information to reduce the risk of errors.