java.security

Class 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 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 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 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.

    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.

        

    • 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 class PermissionCollection
        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 class PermissionCollection
        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 class PermissionCollection
        Returns:
        an enumeration of all the Permissions.

Traduction non disponible

Les API Java ne sont pas encore traduites en français sur l'infobrol. Seule la version anglaise est disponible pour l'instant.

Document créé le 30/08/2006, dernière modification le 04/03/2020
Source du document imprimé : https://www.gaudry.be/java-api-rf-java/security/Permissions.html

L'infobrol est un site personnel dont le contenu n'engage que moi. Le texte est mis à disposition sous licence CreativeCommons(BY-NC-SA). Plus d'info sur les conditions d'utilisation et sur l'auteur.

Références

  1. Consulter le document html Langue du document :fr Manuel PHP : https://docs.oracle.com, Permissions

Ces références et liens indiquent des documents consultés lors de la rédaction de cette page, ou qui peuvent apporter un complément d'information, mais les auteurs de ces sources ne peuvent être tenus responsables du contenu de cette page.
L'auteur de ce site est seul responsable de la manière dont sont présentés ici les différents concepts, et des libertés qui sont prises avec les ouvrages de référence. N'oubliez pas que vous devez croiser les informations de sources multiples afin de diminuer les risques d'erreurs.

Table des matières Haut