/*

 * Copyright 2003-2008 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.remote;

import com.sun.jmx.remote.util.EnvHelp;

import java.io.IOException;

import java.util.ArrayList;

import java.util.List;

import java.util.Map;

import java.util.NoSuchElementException;

import javax.management.MBeanInfo;  // for javadoc

import javax.management.MBeanNotificationInfo;

import javax.management.MBeanRegistration;

import javax.management.MBeanServer;

import javax.management.Notification;

import javax.management.NotificationBroadcasterSupport;

import javax.management.ObjectName;

import javax.management.event.EventClientDelegate;

/**

 * <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>Name of the attribute that specifies whether this connector

      * server can delegate notification handling to the

      * {@linkplain javax.management.event Event Service}.

      * The value associated with

      * this attribute, if any, is a String, which must be equal,

      * ignoring case, to {@code "true"} or {@code "false"}.</p>

      *

      * <p>Not all connector servers will understand this attribute, but the

      * standard {@linkplain javax.management.remote.rmi.RMIConnectorServer

      * RMI Connector Server} does.</p>

      *

      * <p>If this attribute is not present, then the system property of the

      * same name (<code>{@value}</code>) is consulted. If that is not set

      * either, then the Event Service is used if the connector server

      * supports it.</p>

      *

      * @since 1.7

      */

     public static final String DELEGATE_TO_EVENT_SERVICE =

         "jmx.remote.delegate.event.service";

     /**

      * <p>Name of the attribute that specifies whether this connector

      * server simulates the existence of the {@link EventClientDelegate}

      * MBean. The value associated with this attribute, if any, must

      * be a string that is equal to {@code "true"} or {@code "false"},

      * ignoring case. If it is {@code "true"}, then the connector server

      * will simulate an EventClientDelegate MBean, as described in {@link

      * EventClientDelegate#newForwarder}. This MBean is needed for {@link

      * javax.management.event.EventClient EventClient} to function correctly.</p>

      *

      * <p>Not all connector servers will understand this attribute, but the

      * standard {@linkplain javax.management.remote.rmi.RMIConnectorServer

      * RMI Connector Server} does.  For a connector server that understands

      * this attribute, the default value is {@code "true"}.</p>

      *

      * @since 1.7

      */

     public static final String EVENT_CLIENT_DELEGATE_FORWARDER =

         "jmx.remote.event.client.delegate.forwarder";

    /**

     * <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) {

        insertUserMBeanServer(mbeanServer);

    }

    /**

     * <p>Returns the MBean server that this connector server is

     * attached to, or the first in a chain of user-added

     * {@link MBeanServerForwarder}s, if any.</p>

     *

     * @return the MBean server that this connector server is attached

     * to, or null if it is not yet attached to an MBean server.

     *

     * @see #setMBeanServerForwarder

     */

    public synchronized MBeanServer getMBeanServer() {

        return userMBeanServer;

    }

    public synchronized void setMBeanServerForwarder(MBeanServerForwarder mbsf) {

        if (mbsf == null)

            throw new IllegalArgumentException("Invalid null argument: mbsf");

        if (userMBeanServer != null)

            mbsf.setMBeanServer(userMBeanServer);

        insertUserMBeanServer(mbsf);

    }

    /**

     * <p>Remove a forwarder from the chain of forwarders.  The forwarder can

     * be in the system chain or the user chain.  On successful return from

     * this method, the first occurrence in the chain of an object that is

     * {@linkplain Object#equals equal} to {@code mbsf} will have been

     * removed.</p>

     * @param mbsf the forwarder to remove

     * @throws NoSuchElementException if there is no occurrence of {@code mbsf}

     * in the chain.

     */

    public synchronized void removeMBeanServerForwarder(MBeanServerForwarder mbsf) {

        if (mbsf == null)

            throw new IllegalArgumentException("Invalid null argument: mbsf");

            curr = prev.getMBeanServer();

        }

            userMBeanServer = next;

    }

    /*

     * Set userMBeanServer to mbs and arrange for the end of the chain of

     * system MBeanServerForwarders to point to it.  See the comment before

     * the systemMBeanServer and userMBeanServer field declarations.

     */

    private void insertUserMBeanServer(MBeanServer mbs) {

            lastSystemMBSF = (MBeanServerForwarder) mbsi;

        }

        userMBeanServer = mbs;

    }

    /**

     * <p>Returns the first item in the chain of system and then user

     *

     *

     * <p>The <em>user chain</em> is defined by calling {@link

     *

     * <p>This code illustrates how the chains can be traversed:</p>

     *

     * <pre>

     * JMXConnectorServer cs;

     * System.out.println("system chain:");

     * while (true) {

     *     if (mbs == cs.getMBeanServer())

     *         System.out.println("user chain:");

     *     if (!(mbs instanceof MBeanServerForwarder))

     *         break;

     *     MBeanServerForwarder mbsf = (MBeanServerForwarder) mbs;

     *     System.out.println("--forwarder: " + mbsf);

     *     mbs = mbsf.getMBeanServer();

     * }

     * System.out.println("--MBean Server");

     * </pre>

     *

     * @return the first item in the system chain of forwarders.

     *

     *

     *

     */

    }

    /**

     * <p>Returns true if this connector server supports a system chain of

     * {@link MBeanServerForwarder}s.  The default implementation of this

     * method returns false.  Connector servers that do support the system

     * chain must override this method to return true.

     *

     * @return true if this connector server supports the system chain of

     * forwarders.

     */

    public boolean supportsSystemMBeanServerForwarder() {

        return false;

    }

    /**

     * <p>Install {@link MBeanServerForwarder}s in the system chain

     * based on the attributes in the given {@code Map}.  A connector

     * server that {@linkplain #supportsSystemMBeanServerForwarder supports}

     * a system chain of {@code MBeanServerForwarder}s can call this method

     * to add forwarders to that chain based on the contents of {@code env}.

     * In order:</p>

     *

     * <ul>

     *

     * <li>If {@link #EVENT_CLIENT_DELEGATE_FORWARDER} is absent, or is

     *

     * </ul>

     *

     *

     * <p>Attributes in {@code env} that are not listed above are ignored

     * by this method.</p>

     *

     * @throws UnsupportedOperationException if {@link

     * #supportsSystemMBeanServerForwarder} is false.

     */

    protected void installStandardForwarders(Map<String, ?> env) {

        // Remember that forwarders must be added in reverse order!

        boolean ecd = EnvHelp.computeBooleanFromString(

                env, EVENT_CLIENT_DELEGATE_FORWARDER, false, true);

        if (ecd) {

        }

    }

    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>

     *