org.osgi.service.useradmin.Group Maven / Gradle / Ivy
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/*
* Copyright (c) OSGi Alliance (2001, 2008). All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.osgi.service.useradmin;
/**
* A named grouping of roles (Role objects).
*
* Whether or not a given Authorization context implies a
* Group object depends on the members of that Group
* object.
*
* A Group object can have two kinds of members: basic and
* required . A Group object is implied by an
* Authorization context if all of its required members are implied
* and at least one of its basic members is implied.
*
* A Group object must contain at least one basic member in order to
* be implied. In other words, a Group object without any basic
* member roles is never implied by any Authorization context.
*
* A User object always implies itself.
*
* No loop detection is performed when adding members to Group
* objects, which means that it is possible to create circular implications.
* Loop detection is instead done when roles are checked. The semantics is that
* if a role depends on itself (i.e., there is an implication loop), the role is
* not implied.
*
* The rule that a Group object must have at least one basic member
* to be implied is motivated by the following example:
*
*
*
* group foo
* required members: marketing
* basic members: alice, bob
*
*
*
* Privileged operations that require membership in "foo" can be performed only
* by "alice" and "bob", who are in marketing.
*
* If "alice" and "bob" ever transfer to a different department, anybody in
* marketing will be able to assume the "foo" role, which certainly must be
* prevented. Requiring that "foo" (or any Group object for that
* matter) must have at least one basic member accomplishes that.
*
* However, this would make it impossible for a Group object to be
* implied by just its required members. An example where this implication might
* be useful is the following declaration: "Any citizen who is an adult is
* allowed to vote." An intuitive configuration of "voter" would be:
*
*
*
* group voter
* required members: citizen, adult
* basic members:
*
*
*
* However, according to the above rule, the "voter" role could never be assumed
* by anybody, since it lacks any basic members. In order to address this issue
* a predefined role named "user.anyone" can be specified, which is always
* implied. The desired implication of the "voter" group can then be achieved by
* specifying "user.anyone" as its basic member, as follows:
*
*
*
* group voter
* required members: citizen, adult
* basic members: user.anyone
*
*
*
* @version $Revision: 5673 $
*/
public interface Group extends User {
/**
* Adds the specified Role object as a basic member to this
* Group object.
*
* @param role The role to add as a basic member.
*
* @return true if the given role could be added as a basic
* member, and false if this Group object
* already contains a Role object whose name matches that
* of the specified role.
*
* @throws SecurityException If a security manager exists and the caller
* does not have the UserAdminPermission with name
* admin.
*/
public boolean addMember(Role role);
/**
* Adds the specified Role object as a required member to this
* Group object.
*
* @param role The Role object to add as a required member.
*
* @return true if the given Role object could be
* added as a required member, and false if this
* Group object already contains a Role object
* whose name matches that of the specified role.
*
* @throws SecurityException If a security manager exists and the caller
* does not have the UserAdminPermission with name
* admin.
*/
public boolean addRequiredMember(Role role);
/**
* Removes the specified Role object from this Group
* object.
*
* @param role The Role object to remove from this Group
* object.
*
* @return true if the Role object could be removed,
* otherwise false.
*
* @throws SecurityException If a security manager exists and the caller
* does not have the UserAdminPermission with name
* admin.
*/
public boolean removeMember(Role role);
/**
* Gets the basic members of this Group object.
*
* @return The basic members of this Group object, or
* null if this Group object does not contain
* any basic members.
*/
public Role[] getMembers();
/**
* Gets the required members of this Group object.
*
* @return The required members of this Group object, or
* null if this Group object does not contain
* any required members.
*/
public Role[] getRequiredMembers();
}