/* * Copyright (c) 1996, 1997, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation.  Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code 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 * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package java.security.acl; import java.security.Principal; /** * Interface for managing owners of Access Control Lists (ACLs) or ACL * configurations. (Note that the Acl interface in the * <code> java.security.acl </code> package extends this Owner * interface.) The initial owner Principal should be specified as an * argument to the constructor of the class implementing this interface. * * @see java.security.acl.Acl * */public interface Owner {     /**     * Adds an owner. Only owners can modify ACL contents. The caller     * principal must be an owner of the ACL in order to invoke this method.     * That is, only an owner can add another owner. The initial owner is     * configured at ACL construction time.     *     * @param caller the principal invoking this method. It must be an owner     * of the ACL.     *     * @param owner the owner that should be added to the list of owners.     *     * @return true if successful, false if owner is already an owner.     * @exception NotOwnerException if the caller principal is not an owner     * of the ACL.     */    public boolean addOwner(Principal caller, Principal owner)      throws NotOwnerException;     /**     * Deletes an owner. If this is the last owner in the ACL, an exception is     * raised.<p>     *     * The caller principal must be an owner of the ACL in order to invoke     * this method.     *     * @param caller the principal invoking this method. It must be an owner     * of the ACL.     *     * @param owner the owner to be removed from the list of owners.     *     * @return true if the owner is removed, false if the owner is not part     * of the list of owners.     *     * @exception NotOwnerException if the caller principal is not an owner     * of the ACL.     *     * @exception LastOwnerException if there is only one owner left, so that     * deleteOwner would leave the ACL owner-less.     */    public boolean deleteOwner(Principal caller, Principal owner)      throws NotOwnerException, LastOwnerException;     /**     * Returns true if the given principal is an owner of the ACL.     *     * @param owner the principal to be checked to determine whether or not     * it is an owner.     *     * @return true if the passed principal is in the list of owners, false     * if not.     */    public boolean isOwner(Principal owner); }