| /* |
| * Copyright 1999-2004 Sun Microsystems, Inc. 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. Sun designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| * CA 95054 USA or visit www.sun.com if you need additional information or |
| * have any questions. |
| */ |
| |
| package javax.management; |
| |
| |
| /** |
| * <p>Can be implemented by an MBean in order to |
| * carry out operations before and after being registered or unregistered from |
| * the MBean Server. An MBean can also implement this interface in order |
| * to get a reference to the MBean Server and/or its name within that |
| * MBean Server.</p> |
| * |
| * <h4 id="injection">Resource injection</h4> |
| * |
| * <p>As an alternative to implementing {@code MBeanRegistration}, if all that |
| * is needed is the MBean Server or ObjectName then an MBean can use |
| * <em>resource injection</em>.</p> |
| * |
| * <p>If a field in the MBean object has type {@link ObjectName} and has |
| * the {@link javax.annotation.Resource @Resource} annotation, |
| * then the {@code ObjectName} under which the MBean is registered is |
| * assigned to that field during registration. Likewise, if a field has type |
| * {@link MBeanServer} and the <code>@Resource</code> annotation, then it will |
| * be set to the {@code MBeanServer} in which the MBean is registered.</p> |
| * |
| * <p>For example:</p> |
| * |
| * <pre> |
| * public Configuration implements ConfigurationMBean { |
| * @Resource |
| * private volatile MBeanServer mbeanServer; |
| * @Resource |
| * private volatile ObjectName objectName; |
| * ... |
| * void unregisterSelf() throws Exception { |
| * mbeanServer.unregisterMBean(objectName); |
| * } |
| * } |
| * </pre> |
| * |
| * <p>Resource injection can also be used on fields of type |
| * {@link SendNotification} to simplify notification sending. Such a field |
| * will get a reference to an object of type {@code SendNotification} when |
| * the MBean is registered, and it can use this reference to send notifications. |
| * For example:</p> |
| * |
| * <pre> |
| * public Configuration implements ConfigurationMBean { |
| * @Resource |
| * private volatile SendNotification sender; |
| * ... |
| * private void updated() { |
| * Notification n = new Notification(...); |
| * sender.sendNotification(n); |
| * } |
| * } |
| * </pre> |
| * |
| * <p>A field to be injected must not be static. It is recommended that |
| * such fields be declared {@code volatile}.</p> |
| * |
| * <p>It is also possible to use the <code>@Resource</code> annotation on |
| * methods. Such a method must have a {@code void} return type and a single |
| * argument of the appropriate type, for example {@code ObjectName}.</p> |
| * |
| * <p>Any number of fields and methods may have the <code>@Resource</code> |
| * annotation. All fields and methods with type {@code ObjectName} |
| * (for example) will receive the same {@code ObjectName} value.</p> |
| * |
| * <p>Resource injection is available for all types of MBeans, not just |
| * Standard MBeans.</p> |
| * |
| * <p>If an MBean implements the {@link DynamicWrapperMBean} interface then |
| * resource injection happens on the object returned by that interface's |
| * {@link DynamicWrapperMBean#getWrappedObject() getWrappedObject()} method |
| * rather than on the MBean object itself. |
| * |
| * <p>Resource injection happens after the {@link #preRegister preRegister} |
| * method is called (if any), and before the MBean is actually registered |
| * in the MBean Server. If a <code>@Resource</code> method throws |
| * an exception, the effect is the same as if {@code preRegister} had |
| * thrown the exception. In particular it will prevent the MBean from being |
| * registered.</p> |
| * |
| * <p>Resource injection can be used on a field or method where the type |
| * is a parent of the injected type, if the injected type is explicitly |
| * specified in the <code>@Resource</code> annotation. For example:</p> |
| * |
| * <pre> |
| * @Resource(type = MBeanServer.class) |
| * private volatile MBeanServerConnection mbsc; |
| * </pre> |
| * |
| * <p>Formally, suppose <em>R</em> is the type in the <code>@Resource</code> |
| * annotation and <em>T</em> is the type of the method parameter or field. |
| * Then one of <em>R</em> and <em>T</em> must be a subtype of the other |
| * (or they must be the same type). Injection happens if this subtype |
| * is {@code MBeanServer}, {@code ObjectName}, or {@code SendNotification}. |
| * Otherwise the <code>@Resource</code> annotation is ignored.</p> |
| * |
| * <p>Resource injection in MBeans is new in version 2.0 of the JMX API.</p> |
| * |
| * @since 1.5 |
| */ |
| public interface MBeanRegistration { |
| |
| |
| /** |
| * Allows the MBean to perform any operations it needs before |
| * being registered in the MBean Server. If the name of the MBean |
| * is not specified, the MBean can provide a name for its |
| * registration. If any exception is raised, the MBean will not be |
| * registered in the MBean Server. |
| * |
| * @param server The MBean Server in which the MBean will be registered. |
| * |
| * @param name The object name of the MBean. This name is null if |
| * the name parameter to one of the <code>createMBean</code> or |
| * <code>registerMBean</code> methods in the {@link MBeanServer} |
| * interface is null. In that case, this method must return a |
| * non-null ObjectName for the new MBean. |
| * |
| * @return The name under which the MBean is to be registered. |
| * This value must not be null. If the <code>name</code> |
| * parameter is not null, it will usually but not necessarily be |
| * the returned value. |
| * |
| * @exception java.lang.Exception This exception will be caught by |
| * the MBean Server and re-thrown as an {@link |
| * MBeanRegistrationException}. |
| */ |
| public ObjectName preRegister(MBeanServer server, |
| ObjectName name) throws java.lang.Exception; |
| |
| /** |
| * Allows the MBean to perform any operations needed after having been |
| * registered in the MBean server or after the registration has failed. |
| * |
| * @param registrationDone Indicates whether or not the MBean has |
| * been successfully registered in the MBean server. The value |
| * false means that the registration phase has failed. |
| */ |
| public void postRegister(Boolean registrationDone); |
| |
| /** |
| * Allows the MBean to perform any operations it needs before |
| * being unregistered by the MBean server. |
| * |
| * @exception java.lang.Exception This exception will be caught by |
| * the MBean server and re-thrown as an {@link |
| * MBeanRegistrationException}. |
| */ |
| public void preDeregister() throws java.lang.Exception ; |
| |
| /** |
| * Allows the MBean to perform any operations needed after having been |
| * unregistered in the MBean server. |
| */ |
| public void postDeregister(); |
| |
| } |
