/* Acl.java -- An access control list Copyright (C) 1998 Free Software Foundation, Inc. This file is part of GNU Classpath. GNU Classpath is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. GNU Classpath is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with GNU Classpath; see the file COPYING. If not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. Linking this library statically or dynamically with other modules is making a combined work based on this library. Thus, the terms and conditions of the GNU General Public License cover the whole combination. As a special exception, the copyright holders of this library give you permission to link this library with independent modules to produce an executable, regardless of the license terms of these independent modules, and to copy and distribute the resulting executable under terms of your choice, provided that you also meet, for each linked independent module, the terms and conditions of the license of that module. An independent module is a module which is not derived from or based on this library. If you modify this library, you may extend this exception to your version of the library, but you are not obligated to do so. If you do not wish to do so, delete this exception statement from your version. */ package java.security.acl; import java.security.Principal; import java.util.Enumeration; /** * A Java access control list (ACL) is a group of individual ACL entries. * These entries consist of a Principal and a list of * permissions this Principal is either granted or denied. * A given Principal can have at most one positive ACL entry * (i.e., one that grants permissions) and one negative ACL entry (i.e., one * that denies permissions). If a given permission is both granted and * denied, the ACL treats it as if it were never granted or denied. If * both a Principal and a Group to which the * Principal belongs have an ACL entry, the permissions for * the individual Principal take precedence over the * permissions of the Group if there is a conflict. * * Additionally, the ACL interface extends the Owner interface * and so an ACL has owners. Actions which modify the ACL are restricted * to owners. * * @version 0.0 * * @author Aaron M. Renn (arenn@urbanophile.com) */ public interface Acl extends Owner { /** * This method returns the name of this ACL. * * @return The name of this ACL */ String getName(); /** * This method sets the name of the ACL * * @param caller The Principal requesting the action. * @param name The new name for this ACL. * * @exception NotOwnerException If the caller is not an owner of this ACL. */ void setName(Principal caller, String name) throws NotOwnerException; /** * This method adds the specified entry to the ACL * * @param caller The Principal requesting the addition * @param entry The ACL entry to add * * @return true if the entry was added, false * if there is already an entry of the same type for the * Principal. * * @exception NotOwnerException If the caller is not an owner of this ACL. */ boolean addEntry(Principal caller, AclEntry entry) throws NotOwnerException; /** * This method delets the specified entry from the ACL * * @param caller The Principal requesting the deletion. * @param entry The ACL entry to delete * * @return true if the entry was deleted, or false * if this entry was not part of the ACL to begin with * * @exception NotOwnerException If the caller is not an owner of this ACL. */ boolean removeEntry(Principal caller, AclEntry entry) throws NotOwnerException; /** * This method returns a list of all the entries in the ACL as an * Enumeration. * * @return An enumeration of the ACL entries */ Enumeration entries(); /** * This method tests whether or not the specified Principal * has the specified Permission * * @param user The Principal to test * @param perm The Permission to test for * * @return true if the user has been granted the permission, * false otherwise */ boolean checkPermission(Principal user, Permission perm); /** * This method returns a list of Permission's that are granted * to a particular Principal. This includes any permissions * that are granted to Group's to which the Principal * belongs unless they are overridden by a negative ACL. This permission * list is returned as an Enumeration. * * @param user The Principal to retrieve permissions for. * * @return A list of permissions for the Principal. */ Enumeration getPermissions(Principal user); /** * This method returns the ACL as a String * * @return A String representation of this ACL */ String toString(); }
