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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

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 * 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).

 *

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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} 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);

}