/* * Copyright (c) 1996, 2006, 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 sun.security.acl; import java.util.*;import java.security.*;import java.security.acl.*; /** * Class implementing the Owner interface. The * initial owner principal is configured as * part of the constructor. * @author      Satish Dharmaraj */public class OwnerImpl implements Owner {    private Group ownerGroup;     public OwnerImpl(Principal owner) {        ownerGroup = new GroupImpl("AclOwners");        ownerGroup.addMember(owner);    }     /**     * Adds an owner. Owners can modify ACL contents and can disassociate     * ACLs from the objects they protect in the AclConfig interface.     * The caller principal must be a part of the owners list of the ACL in     * order to invoke this method. The initial owner is configured     * at ACL construction time.     * @param caller the principal who is invoking this method.     * @param owner The owner that should be added to the owners list.     * @return true if success, false if already an owner.     * @exception NotOwnerException if the caller principal is not on     * the owners list of the Acl.     */    public synchronized boolean addOwner(Principal caller, Principal owner)      throws NotOwnerException    {        if (!isOwner(caller))            throw new NotOwnerException();         ownerGroup.addMember(owner);        return false;    }     /**     * Delete owner. If this is the last owner in the ACL, an exception is     * raised.     * The caller principal must be a part of the owners list of the ACL in     * order to invoke this method.     * @param caller the principal who is invoking this method.     * @param owner The owner to be removed from the owners list.     * @return true if the owner is removed, false if the owner is not part     * of the owners list.     * @exception NotOwnerException if the caller principal is not on     * the owners list of the Acl.     * @exception LastOwnerException if there is only one owner left in the group, then     * deleteOwner would leave the ACL owner-less. This exception is raised in such a case.     */    public synchronized boolean deleteOwner(Principal caller, Principal owner)      throws NotOwnerException, LastOwnerException    {        if (!isOwner(caller))            throw new NotOwnerException();         Enumeration<? extends Principal> e = ownerGroup.members();        //        // check if there is atleast 2 members left.        //        Object o = e.nextElement();        if (e.hasMoreElements())            return ownerGroup.removeMember(owner);        else            throw new LastOwnerException();     }     /**     * returns if the given principal belongs to the owner list.     * @param owner The owner to check if part of the owners list     * @return true if the passed principal is in the owner list, false if not.     */    public synchronized boolean isOwner(Principal owner) {        return ownerGroup.isMember(owner);    }}