Source for javax.management.PersistentMBean

   1: /* PersistentMBean.java -- Interface for beans that should persist.
   2:    Copyright (C) 2007 Free Software Foundation, Inc.
   3: 
   4: This file is part of GNU Classpath.
   5: 
   6: GNU Classpath is free software; you can redistribute it and/or modify
   7: it under the terms of the GNU General Public License as published by
   8: the Free Software Foundation; either version 2, or (at your option)
   9: any later version.
  10: 
  11: GNU Classpath is distributed in the hope that it will be useful, but
  12: WITHOUT ANY WARRANTY; without even the implied warranty of
  13: MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14: General Public License for more details.
  15: 
  16: You should have received a copy of the GNU General Public License
  17: along with GNU Classpath; see the file COPYING.  If not, write to the
  18: Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19: 02110-1301 USA.
  20: 
  21: Linking this library statically or dynamically with other modules is
  22: making a combined work based on this library.  Thus, the terms and
  23: conditions of the GNU General Public License cover the whole
  24: combination.
  25: 
  26: As a special exception, the copyright holders of this library give you
  27: permission to link this library with independent modules to produce an
  28: executable, regardless of the license terms of these independent
  29: modules, and to copy and distribute the resulting executable under
  30: terms of your choice, provided that you also meet, for each linked
  31: independent module, the terms and conditions of the license of that
  32: module.  An independent module is a module which is not derived from
  33: or based on this library.  If you modify this library, you may extend
  34: this exception to your version of the library, but you are not
  35: obligated to do so.  If you do not wish to do so, delete this
  36: exception statement from your version. */
  37: 
  38: package javax.management;
  39: 
  40: /**
  41:  * Beans may implement this interface in order to become
  42:  * persistent.  The {@link #load()} method should be
  43:  * called on construction in order to reload the stored
  44:  * state.  The {@link #store()} method should be called
  45:  * sometime during the bean's lifetime in order to create
  46:  * a persistent copy of the bean's instance data.  This
  47:  * method may also be called by the {@link MBeanServer}
  48:  * as a result of the {@link Descriptor} of an
  49:  * {@link javax.management.modelmbean.ModelMBean}.
  50:  *
  51:  * @author Andrew John Hughes (gnu_andrew@member.fsf.org)
  52:  * @since 1.5
  53:  */
  54: public interface PersistentMBean
  55: {
  56: 
  57:   /**
  58:    * Instantiates the bean with the data previously stored
  59:    * using a call to {@link #store()}.  The data stored can
  60:    * include values held by attributes as well as those returned
  61:    * by operations.  This method should be called during
  62:    * construction or initialisation of the bean, before
  63:    * it becomes registered with an {@link MBeanServer}.
  64:    *
  65:    * @throws MBeanException if persistence is not supported,
  66:    *                        or another exception is thrown
  67:    *                        (which this then wraps).
  68:    * @throws RuntimeOperationsException if the persistence
  69:    *                                    mechanism throws an
  70:    *                                    exception.
  71:    * @throws InstanceNotFoundException if the bean can not
  72:    *                                   be found in the
  73:    *                                   persistent store.
  74:    */
  75:   void load()
  76:     throws MBeanException, RuntimeOperationsException,
  77:        InstanceNotFoundException;
  78: 
  79:   /**
  80:    * <p>
  81:    * Captures the current state of the bean and stores it
  82:    * for future retrieval by the {@link #load()} method.
  83:    * The data stored can include values held by attributes
  84:    * as well as those returned by operations.
  85:    * </p>
  86:    * <p>
  87:    * Whether the state is stored or not depends on the
  88:    * <code>persistPolicy</code> field of the MBean/attribute
  89:    * descriptor.  The state should be stored if the policy
  90:    * is set to any of the following:
  91:    * </p>
  92:    * <ul>
  93:    * <li><code>always</code></li>
  94:    * <li><code>onTimer</code> and <code>now</code> is
  95:    * greater than or equal to <code>lastPersistTime +
  96:    * persistPeriod</code>.</li>
  97:    * <li><code>noMoreOftenThan</code> and <code>now</code> is
  98:    * greater than or equal to <code>lastPersistTime +
  99:    * persistPeriod</code>.</li>
 100:    * <li>onUnregister</li>
 101:    * </ul>
 102:    * <p>If the policy is set to any of the following, the state
 103:    * should not be stored:</p>
 104:    * <ul>
 105:    * <li><code>never</code></li>
 106:    * <li><code>onUpdate</code></li>
 107:    * <li><code>onTimer</code> and <code>now</code> is
 108:    * less than <code>lastPersistTime + persistPeriod</code>.
 109:    * </li>
 110:    * </ul>
 111:    *
 112:    * @throws MBeanException if persistence is not supported,
 113:    *                        or another exception is thrown
 114:    *                        (which this then wraps).
 115:    * @throws RuntimeOperationsException if the persistence
 116:    *                                    mechanism throws an
 117:    *                                    exception.
 118:    * @throws InstanceNotFoundException if the persistent
 119:    *                                   store can not be found
 120:    *                                   or accessed.
 121:    */
 122:   void store()
 123:     throws MBeanException, RuntimeOperationsException,
 124:        InstanceNotFoundException;
 125: 
 126: }