/*
 * @(#)Refreshable.java	1.9 03/12/19
 *
 * Copyright 2004 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */

package javax.security.auth;

/**
 * Objects such as credentials may optionally implement this
 * interface to provide the capability to refresh itself.
 * For example, a credential with a particular time-restricted lifespan 
 * may implement this interface to allow callers to refresh the time period
 * for which it is valid.
 *
 * @version 1.9, 12/19/03
 * @see javax.security.auth.Subject
 */
public interface Refreshable {

    /**
     * Determine if this <code>Object</code> is current.
     *
     * <p>
     *
     * @return true if this <code>Object</code> is currently current,
     *		false otherwise.
     */
    boolean isCurrent();
 
    /**
     * Update or extend the validity period for this
     * <code>Object</code>.
     *
     * <p>
     *
     * @exception SecurityException if the caller does not have permission
     *		to update or extend the validity period for this
     *		<code>Object</code>. <p>
     *
     * @exception RefreshFailedException if the refresh attempt failed.
     */
    void refresh() throws RefreshFailedException;
}