ojluni/src/main/java/javax/management/PersistentMBean.java

/*
 * Copyright (c) 2000, 2005, 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.
 *
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/*
 * @author    IBM Corp.
 *
 * Copyright IBM Corp. 1999-2000.  All rights reserved.
 */

package javax.management;

import javax.management.MBeanException;
import javax.management.RuntimeOperationsException;
import javax.management.InstanceNotFoundException;

/**
 *  This class is the interface to be implemented by MBeans that are meant to be
 *  persistent.  MBeans supporting this interface should call the load method during
 *  construction in order to prime the MBean from the persistent store.
 *  In the case of a ModelMBean, the store method should be called by the MBeanServer based on the descriptors in
 *  the ModelMBean or by the MBean itself during normal processing of the ModelMBean.
 *
 * @since 1.5
 */
public interface PersistentMBean {


    /**
     * Instantiates thisMBean instance with the data found for
     * the MBean in the persistent store.  The data loaded could include
     * attribute and operation values.
     *
     * This method should be called during construction or initialization of this instance,
     * and before the MBean is registered with the MBeanServer.
     *
     * @exception MBeanException Wraps another exception or persistence is not supported
     * @exception RuntimeOperationsException Wraps exceptions from the persistence mechanism
     * @exception InstanceNotFoundException Could not find or load this MBean from persistent
     *                                      storage
     */
    public void load()
    throws MBeanException, RuntimeOperationsException, InstanceNotFoundException;

    /**
     * Captures the current state of this MBean instance and
     * writes it out to the persistent store.  The state stored could include
     * attribute and operation values. If one of these methods of persistence is
     * not supported a "serviceNotFound" exception will be thrown.
     * <P>
     * Persistence policy from the MBean and attribute descriptor is used to guide execution
     * of this method. The MBean should be stored if 'persistPolicy' field is:
     * <PRE>  != "never"
     *   = "always"
     *   = "onTimer" and now > 'lastPersistTime' + 'persistPeriod'
     *   = "NoMoreOftenThan" and now > 'lastPersistTime' + 'persistPeriod'
     *   = "onUnregister"
     * <P>
     * Do not store the MBean if 'persistPolicy' field is:
     *    = "never"
     *    = "onUpdate"
     *    = "onTimer" && now < 'lastPersistTime' + 'persistPeriod'
     * <P></PRE>
     *
     * @exception MBeanException Wraps another exception or persistence is not supported
     * @exception RuntimeOperationsException Wraps exceptions from the persistence mechanism
     * @exception InstanceNotFoundException Could not find/access the persistent store
     */
    public void store()
    throws MBeanException, RuntimeOperationsException, InstanceNotFoundException;

}