Package org.wicketstuff.security.hive.authorization

Class Permission

  • All Implemented Interfaces:
    Serializable
    Direct Known Subclasses:
    ActionPermission
    public abstract class Permission
extends Object
implements Serializable
    Abstract class for representing access to a system resource. All permissions have a name (whose interpretation depends on the subclass), as well as abstract functions for defining the semantics of the particular Permission subclass.

    Most Permission objects also include an "actions" list that tells the actions that are permitted for the object. For example, for a java.io.FilePermission object, the permission name is the pathname of a file (or directory), and the actions list (such as "read, write") specifies which actions are granted for the specified file (or for files in the specified directory). The actions list is optional for Permission objects, such as java.lang.RuntimePermission, that don't need such a list; you either have the named permission (such as "system.exit") or you don't. See ActionPermission.

    An important method that must be implemented by each subclass is the implies method to compare Permissions. Basically, "permission p1 implies permission p2" means that if one is granted permission p1, one is naturally granted permission p2. Thus, this is not an equality test, but rather more of a subset test.

    Permission objects are similar to String objects in that they are immutable once they have been created. Subclasses should not provide methods that can change the state of a permission once it has been created. All permissions must at least have a public constructor accepting a String parameter which will be used as name for the permission. Note that the ActionPermission should also have a 2 argument constructor accepting a string as the name and a second WaspAction parameter to indicate which actions are allowed.

    Author:
    marrink
    See Also:
    Serialized Form

    • Constructor Detail

      • Permission

        public Permission​(String name)
        Constructs a permission with a certain name.
        Parameters:
        name -

    • Method Detail

      • implies

        public abstract boolean implies​(Permission permission)
        Check if this permission implies the specified permission.
        Parameters:
        permission -
        Returns:
        true if this implies the permission, false otherwise.

      • equals

        public abstract boolean equals​(Object obj)
        Checks two Permission objects for equality.

        Do not use the equals method for making access control decisions; use the implies method.

        Overrides:
        equals in class Object
        Parameters:
        obj - the object we are testing for equality with this object.
        Returns:
        true if both Permission objects are equivalent.

      • hashCode

        public abstract int hashCode()
        Returns the hash code value for this Permission object.

        The required hashCode behavior for Permission Objects is the following:

        • Whenever it is invoked on the same Permission object more than once during an execution of a Java application, the hashCode method must consistently return the same integer. This integer need not remain consistent from one execution of an application to another execution of the same application.

        • If two Permission objects are equal according to the equals method, then calling the hashCode method on each of the two Permission objects must produce the same integer result.
        Overrides:
        hashCode in class Object
        Returns:
        a hash code value for this object.

      • getActions

        public abstract String getActions()
        Returns the actions as a String. This is abstract so subclasses can defer creating a String representation until one is needed. Subclasses should always return actions in what they consider to be their canonical form. For example, two FilePermission objects created via the following: 
         perm1 = new FilePermission(p1, "read,write");
 perm2 = new FilePermission(p2, "write,read");
        both return "read,write" when the getActions method is invoked.
        Returns:
        the actions of this Permission.

      • getName

        public final String getName()
        Returns the name of this Permission. For example, in the case of a org.wicketstuff.security.hive.authorization.permissions.ComponentPermission , the name will be a component path.
        Returns:
        the name of this Permission.