| /* | |
| * Copyright (c) 2003, 2022, 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. | |
| * | |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA | |
| * or visit www.oracle.com if you need additional information or have any | |
| * questions. | |
| */ | |
| package javax.management.remote; | |
| import java.io.IOException; | |
| import java.util.ArrayList; | |
| import java.util.List; | |
| import java.util.Map; | |
| import javax.management.MBeanNotificationInfo; | |
| import javax.management.MBeanRegistration; | |
| import javax.management.MBeanServer; | |
| import javax.management.Notification; | |
| import javax.management.NotificationBroadcasterSupport; | |
| import javax.management.ObjectName; | |
| /** | |
| * <p>Superclass of every connector server. A connector server is | |
| * attached to an MBean server. It listens for client connection | |
| * requests and creates a connection for each one.</p> | |
| * | |
| * <p>A connector server is associated with an MBean server either by | |
| * registering it in that MBean server, or by passing the MBean server | |
| * to its constructor.</p> | |
| * | |
| * <p>A connector server is inactive when created. It only starts | |
| * listening for client connections when the {@link #start() start} | |
| * method is called. A connector server stops listening for client | |
| * connections when the {@link #stop() stop} method is called or when | |
| * the connector server is unregistered from its MBean server.</p> | |
| * | |
| * <p>Stopping a connector server does not unregister it from its | |
| * MBean server. A connector server once stopped cannot be | |
| * restarted.</p> | |
| * | |
| * <p>Each time a client connection is made or broken, a notification | |
| * of class {@link JMXConnectionNotification} is emitted.</p> | |
| * | |
| * @since 1.5 | |
| */ | |
| public abstract class JMXConnectorServer | |
| extends NotificationBroadcasterSupport | |
| implements JMXConnectorServerMBean, MBeanRegistration, JMXAddressable { | |
| /** | |
| * <p>Name of the attribute that specifies the authenticator for a | |
| * connector server. The value associated with this attribute, if | |
| * any, must be an object that implements the interface {@link | |
| * JMXAuthenticator}.</p> | |
| */ | |
| public static final String AUTHENTICATOR = | |
| "jmx.remote.authenticator"; | |
| /** | |
| * <p>Constructs a connector server that will be registered as an | |
| * MBean in the MBean server it is attached to. This constructor | |
| * is typically called by one of the <code>createMBean</code> | |
| * methods when creating, within an MBean server, a connector | |
| * server that makes it available remotely.</p> | |
| */ | |
| public JMXConnectorServer() { | |
| this(null); | |
| } | |
| /** | |
| * <p>Constructs a connector server that is attached to the given | |
| * MBean server. A connector server that is created in this way | |
| * can be registered in a different MBean server, or not registered | |
| * in any MBean server.</p> | |
| * | |
| * @param mbeanServer the MBean server that this connector server | |
| * is attached to. Null if this connector server will be attached | |
| * to an MBean server by being registered in it. | |
| */ | |
| public JMXConnectorServer(MBeanServer mbeanServer) { | |
| this.mbeanServer = mbeanServer; | |
| } | |
| /** | |
| * <p>Returns the MBean server that this connector server is | |
| * attached to.</p> | |
| * | |
| * @return the MBean server that this connector server is attached | |
| * to, or null if it is not yet attached to an MBean server. | |
| */ | |
| public synchronized MBeanServer getMBeanServer() { | |
| return mbeanServer; | |
| } | |
| public synchronized void setMBeanServerForwarder(MBeanServerForwarder mbsf) | |
| { | |
| if (mbsf == null) | |
| throw new IllegalArgumentException("Invalid null argument: mbsf"); | |
| if (mbeanServer != null) mbsf.setMBeanServer(mbeanServer); | |
| mbeanServer = mbsf; | |
| } | |
| public String[] getConnectionIds() { | |
| synchronized (connectionIds) { | |
| return connectionIds.toArray(new String[connectionIds.size()]); | |
| } | |
| } | |
| /** | |
| * <p>Returns a client stub for this connector server. A client | |
| * stub is a serializable object whose {@link | |
| * JMXConnector#connect(Map) connect} method can be used to make | |
| * one new connection to this connector server.</p> | |
| * | |
| * <p>A given connector need not support the generation of client | |
| * stubs. However, the connectors specified by the JMX Remote API do | |
| * (JMXMP Connector and RMI Connector).</p> | |
| * | |
| * <p>The default implementation of this method uses {@link | |
| * #getAddress} and {@link JMXConnectorFactory} to generate the | |
| * stub, with code equivalent to the following:</p> | |
| * | |
| * <pre> | |
| * JMXServiceURL addr = {@link #getAddress() getAddress()}; | |
| * return {@link JMXConnectorFactory#newJMXConnector(JMXServiceURL, Map) | |
| * JMXConnectorFactory.newJMXConnector(addr, env)}; | |
| * </pre> | |
| * | |
| * <p>A connector server for which this is inappropriate must | |
| * override this method so that it either implements the | |
| * appropriate logic or throws {@link | |
| * UnsupportedOperationException}.</p> | |
| * | |
| * @param env client connection parameters of the same sort that | |
| * could be provided to {@link JMXConnector#connect(Map) | |
| * JMXConnector.connect(Map)}. Can be null, which is equivalent | |
| * to an empty map. | |
| * | |
| * @return a client stub that can be used to make a new connection | |
| * to this connector server. | |
| * | |
| * @exception UnsupportedOperationException if this connector | |
| * server does not support the generation of client stubs. | |
| * | |
| * @exception IllegalStateException if the JMXConnectorServer is | |
| * not started (see {@link JMXConnectorServerMBean#isActive()}). | |
| * | |
| * @exception IOException if a communications problem means that a | |
| * stub cannot be created. | |
| **/ | |
| public JMXConnector toJMXConnector(Map<String,?> env) | |
| throws IOException | |
| { | |
| if (!isActive()) throw new | |
| IllegalStateException("Connector is not active"); | |
| JMXServiceURL addr = getAddress(); | |
| return JMXConnectorFactory.newJMXConnector(addr, env); | |
| } | |
| /** | |
| * <p>Returns an array indicating the notifications that this MBean | |
| * sends. The implementation in <code>JMXConnectorServer</code> | |
| * returns an array with one element, indicating that it can emit | |
| * notifications of class {@link JMXConnectionNotification} with | |
| * the types defined in that class. A subclass that can emit other | |
| * notifications should return an array that contains this element | |
| * plus descriptions of the other notifications.</p> | |
| * | |
| * @return the array of possible notifications. | |
| */ | |
| @Override | |
| public MBeanNotificationInfo[] getNotificationInfo() { | |
| final String[] types = { | |
| JMXConnectionNotification.OPENED, | |
| JMXConnectionNotification.CLOSED, | |
| JMXConnectionNotification.FAILED, | |
| }; | |
| final String className = JMXConnectionNotification.class.getName(); | |
| final String description = | |
| "A client connection has been opened or closed"; | |
| return new MBeanNotificationInfo[] { | |
| new MBeanNotificationInfo(types, className, description), | |
| }; | |
| } | |
| /** | |
| * <p>Called by a subclass when a new client connection is opened. | |
| * Adds <code>connectionId</code> to the list returned by {@link | |
| * #getConnectionIds()}, then emits a {@link | |
| * JMXConnectionNotification} with type {@link | |
| * JMXConnectionNotification#OPENED}.</p> | |
| * | |
| * @param connectionId the ID of the new connection. This must be | |
| * different from the ID of any connection previously opened by | |
| * this connector server. | |
| * | |
| * @param message the message for the emitted {@link | |
| * JMXConnectionNotification}. Can be null. See {@link | |
| * Notification#getMessage()}. | |
| * | |
| * @param userData the <code>userData</code> for the emitted | |
| * {@link JMXConnectionNotification}. Can be null. See {@link | |
| * Notification#getUserData()}. | |
| * | |
| * @exception NullPointerException if <code>connectionId</code> is | |
| * null. | |
| */ | |
| protected void connectionOpened(String connectionId, | |
| String message, | |
| Object userData) { | |
| if (connectionId == null) | |
| throw new NullPointerException("Illegal null argument"); | |
| synchronized (connectionIds) { | |
| connectionIds.add(connectionId); | |
| } | |
| sendNotification(JMXConnectionNotification.OPENED, connectionId, | |
| message, userData); | |
| } | |
| /** | |
| * <p>Called by a subclass when a client connection is closed | |
| * normally. Removes <code>connectionId</code> from the list returned | |
| * by {@link #getConnectionIds()}, then emits a {@link | |
| * JMXConnectionNotification} with type {@link | |
| * JMXConnectionNotification#CLOSED}.</p> | |
| * | |
| * @param connectionId the ID of the closed connection. | |
| * | |
| * @param message the message for the emitted {@link | |
| * JMXConnectionNotification}. Can be null. See {@link | |
| * Notification#getMessage()}. | |
| * | |
| * @param userData the <code>userData</code> for the emitted | |
| * {@link JMXConnectionNotification}. Can be null. See {@link | |
| * Notification#getUserData()}. | |
| * | |
| * @exception NullPointerException if <code>connectionId</code> | |
| * is null. | |
| */ | |
| protected void connectionClosed(String connectionId, | |
| String message, | |
| Object userData) { | |
| if (connectionId == null) | |
| throw new NullPointerException("Illegal null argument"); | |
| synchronized (connectionIds) { | |
| connectionIds.remove(connectionId); | |
| } | |
| sendNotification(JMXConnectionNotification.CLOSED, connectionId, | |
| message, userData); | |
| } | |
| /** | |
| * <p>Called by a subclass when a client connection fails. | |
| * Removes <code>connectionId</code> from the list returned by | |
| * {@link #getConnectionIds()}, then emits a {@link | |
| * JMXConnectionNotification} with type {@link | |
| * JMXConnectionNotification#FAILED}.</p> | |
| * | |
| * @param connectionId the ID of the failed connection. | |
| * | |
| * @param message the message for the emitted {@link | |
| * JMXConnectionNotification}. Can be null. See {@link | |
| * Notification#getMessage()}. | |
| * | |
| * @param userData the <code>userData</code> for the emitted | |
| * {@link JMXConnectionNotification}. Can be null. See {@link | |
| * Notification#getUserData()}. | |
| * | |
| * @exception NullPointerException if <code>connectionId</code> is | |
| * null. | |
| */ | |
| protected void connectionFailed(String connectionId, | |
| String message, | |
| Object userData) { | |
| if (connectionId == null) | |
| throw new NullPointerException("Illegal null argument"); | |
| synchronized (connectionIds) { | |
| connectionIds.remove(connectionId); | |
| } | |
| sendNotification(JMXConnectionNotification.FAILED, connectionId, | |
| message, userData); | |
| } | |
| private void sendNotification(String type, String connectionId, | |
| String message, Object userData) { | |
| Notification notif = | |
| new JMXConnectionNotification(type, | |
| getNotificationSource(), | |
| connectionId, | |
| nextSequenceNumber(), | |
| message, | |
| userData); | |
| sendNotification(notif); | |
| } | |
| private synchronized Object getNotificationSource() { | |
| if (myName != null) | |
| return myName; | |
| else | |
| return this; | |
| } | |
| private static long nextSequenceNumber() { | |
| synchronized (sequenceNumberLock) { | |
| return sequenceNumber++; | |
| } | |
| } | |
| // implements MBeanRegistration | |
| /** | |
| * <p>Called by an MBean server when this connector server is | |
| * registered in that MBean server. This connector server becomes | |
| * attached to the MBean server and its {@link #getMBeanServer()} | |
| * method will return <code>mbs</code>.</p> | |
| * | |
| * <p>If this connector server is already attached to an MBean | |
| * server, this method has no effect. The MBean server it is | |
| * attached to is not necessarily the one it is being registered | |
| * in.</p> | |
| * | |
| * @param mbs the MBean server in which this connection server is | |
| * being registered. | |
| * | |
| * @param name The object name of the MBean. | |
| * | |
| * @return The name under which the MBean is to be registered. | |
| * | |
| * @exception NullPointerException if <code>mbs</code> or | |
| * <code>name</code> is null. | |
| */ | |
| public synchronized ObjectName preRegister(MBeanServer mbs, | |
| ObjectName name) { | |
| if (mbs == null || name == null) | |
| throw new NullPointerException("Null MBeanServer or ObjectName"); | |
| if (mbeanServer == null) { | |
| mbeanServer = mbs; | |
| myName = name; | |
| } | |
| return name; | |
| } | |
| public void postRegister(Boolean registrationDone) { | |
| // do nothing | |
| } | |
| /** | |
| * <p>Called by an MBean server when this connector server is | |
| * unregistered from that MBean server. If this connector server | |
| * was attached to that MBean server by being registered in it, | |
| * and if the connector server is still active, | |
| * then unregistering it will call the {@link #stop stop} method. | |
| * If the <code>stop</code> method throws an exception, the | |
| * unregistration attempt will fail. It is recommended to call | |
| * the <code>stop</code> method explicitly before unregistering | |
| * the MBean.</p> | |
| * | |
| * @exception IOException if thrown by the {@link #stop stop} method. | |
| */ | |
| public synchronized void preDeregister() throws Exception { | |
| if (myName != null && isActive()) { | |
| stop(); | |
| myName = null; // just in case stop is buggy and doesn't stop | |
| } | |
| } | |
| public void postDeregister() { | |
| myName = null; | |
| } | |
| /** | |
| * The MBeanServer used by this server to execute a client request. | |
| */ | |
| private MBeanServer mbeanServer = null; | |
| /** | |
| * The name used to registered this server in an MBeanServer. | |
| * It is null if the this server is not registered or has been unregistered. | |
| */ | |
| private ObjectName myName; | |
| private final List<String> connectionIds = new ArrayList<>(); | |
| private static final int[] sequenceNumberLock = new int[0]; | |
| private static long sequenceNumber; | |
| } |