/*

 * Copyright (c) 2000, 2017, 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.relation;

import static com.sun.jmx.mbeanserver.Util.cast;

import static com.sun.jmx.defaults.JmxProperties.RELATION_LOGGER;

import com.sun.jmx.mbeanserver.GetPropertyAction;

import java.io.IOException;

import java.io.ObjectInputStream;

import java.io.ObjectOutputStream;

import java.io.ObjectStreamField;

import java.security.AccessController;

import java.util.List;

import java.util.Vector;

import javax.management.MBeanServerNotification;

import javax.management.Notification;

import javax.management.NotificationFilterSupport;

import javax.management.ObjectName;

import java.util.List;

import java.lang.System.Logger.Level;

import java.util.Vector;

/**

 * Filter for {@link MBeanServerNotification}.

 * This filter filters MBeanServerNotification notifications by

 * selecting the ObjectNames of interest and the operations (registration,

 * unregistration, both) of interest (corresponding to notification

 * types).

 *

 * <p>The <b>serialVersionUID</b> of this class is <code>2605900539589789736L</code>.

 *

 * @since 1.5

 */

@SuppressWarnings("serial")  // serialVersionUID must be constant

public class MBeanServerNotificationFilter extends NotificationFilterSupport {

    // Serialization compatibility stuff:

    // Two serial forms are supported in this class. The selected form depends

    // on system property "jmx.serial.form":

    //  - "1.0" for JMX 1.0

    //  - any other value for JMX 1.1 and higher

    //

    // Serial version for old serial form

    private static final long oldSerialVersionUID = 6001782699077323605L;

    //

    // Serial version for new serial form

    private static final long newSerialVersionUID = 2605900539589789736L;

    //

    // Serializable fields in old serial form

    private static final ObjectStreamField[] oldSerialPersistentFields =

    {

      new ObjectStreamField("mySelectObjNameList", Vector.class),

      new ObjectStreamField("myDeselectObjNameList", Vector.class)

    };

    //

    // Serializable fields in new serial form

    private static final ObjectStreamField[] newSerialPersistentFields =

    {

      new ObjectStreamField("selectedNames", List.class),

      new ObjectStreamField("deselectedNames", List.class)

    };

    //

    // Actual serial version and serial form

    private static final long serialVersionUID;

    /**

     * @serialField selectedNames List List of {@link ObjectName}s of interest

     *         <ul>

     *         <li><code>null</code> means that all {@link ObjectName}s are implicitly selected

     *         (check for explicit deselections)</li>

     *         <li>Empty vector means that no {@link ObjectName} is explicitly selected</li>

     *         </ul>

     * @serialField deselectedNames List List of {@link ObjectName}s with no interest

     *         <ul>

     *         <li><code>null</code> means that all {@link ObjectName}s are implicitly deselected

     *         (check for explicit selections))</li>

     *         <li>Empty vector means that no {@link ObjectName} is explicitly deselected</li>

     *         </ul>

     */

    private static final ObjectStreamField[] serialPersistentFields;

    private static boolean compat = false;

    static {

        try {

            GetPropertyAction act = new GetPropertyAction("jmx.serial.form");

            String form = AccessController.doPrivileged(act);

            compat = (form != null && form.equals("1.0"));

        } catch (Exception e) {

            // OK : Too bad, no compat with 1.0

        }

        if (compat) {

            serialPersistentFields = oldSerialPersistentFields;

            serialVersionUID = oldSerialVersionUID;

        } else {

            serialPersistentFields = newSerialPersistentFields;

            serialVersionUID = newSerialVersionUID;

        }

    }

    //

    // END Serialization compatibility stuff

    //

    // Private members

    //

    /**

     * @serial List of {@link ObjectName}s of interest

     *         <ul>

     *         <li><code>null</code> means that all {@link ObjectName}s are implicitly selected

     *         (check for explicit deselections)</li>

     *         <li>Empty vector means that no {@link ObjectName} is explicitly selected</li>

     *         </ul>

     */

    private List<ObjectName> selectedNames = new Vector<ObjectName>();

    /**

     * @serial List of {@link ObjectName}s with no interest

     *         <ul>

     *         <li><code>null</code> means that all {@link ObjectName}s are implicitly deselected

     *         (check for explicit selections))</li>

     *         <li>Empty vector means that no {@link ObjectName} is explicitly deselected</li>

     *         </ul>

     */

    private List<ObjectName> deselectedNames = null;

    //

    // Constructor

    //

    /**

     * Creates a filter selecting all MBeanServerNotification notifications for

     * all ObjectNames.

     */

    public MBeanServerNotificationFilter() {

        super();

        RELATION_LOGGER.log(Level.TRACE, "ENTRY");

        enableType(MBeanServerNotification.REGISTRATION_NOTIFICATION);

        enableType(MBeanServerNotification.UNREGISTRATION_NOTIFICATION);

        RELATION_LOGGER.log(Level.TRACE, "RETURN");

        return;

    }

    //

    // Accessors

    //

    /**

     * Disables any MBeanServerNotification (all ObjectNames are

     * deselected).

     */

    public synchronized void disableAllObjectNames() {

        RELATION_LOGGER.log(Level.TRACE, "ENTRY");

        selectedNames = new Vector<ObjectName>();

        deselectedNames = null;

        RELATION_LOGGER.log(Level.TRACE, "RETURN");

        return;

    }

    /**

     * Disables MBeanServerNotifications concerning given ObjectName.

     *

     * @param objectName  ObjectName no longer of interest

     *

     * @exception IllegalArgumentException  if the given ObjectName is null

     */

    public synchronized void disableObjectName(ObjectName objectName)

        throws IllegalArgumentException {

        if (objectName == null) {

            String excMsg = "Invalid parameter.";

            throw new IllegalArgumentException(excMsg);

        }

        RELATION_LOGGER.log(Level.TRACE, "ENTRY {0}" + objectName);

        // Removes from selected ObjectNames, if present

        if (selectedNames != null) {

            if (selectedNames.size() != 0) {

                selectedNames.remove(objectName);

            }

        }

        // Adds it in deselected ObjectNames

        if (deselectedNames != null) {

            // If all are deselected, no need to do anything :)

            if (!(deselectedNames.contains(objectName))) {

                // ObjectName was not already deselected

                deselectedNames.add(objectName);

            }

        }

        RELATION_LOGGER.log(Level.TRACE, "RETURN");

        return;

    }

    /**

     * Enables all MBeanServerNotifications (all ObjectNames are selected).

     */

    public synchronized void enableAllObjectNames() {

        RELATION_LOGGER.log(Level.TRACE, "ENTRY");

        selectedNames = null;

        deselectedNames = new Vector<ObjectName>();

        RELATION_LOGGER.log(Level.TRACE, "RETURN");

        return;

    }

    /**

     * Enables MBeanServerNotifications concerning given ObjectName.

     *

     * @param objectName  ObjectName of interest

     *

     * @exception IllegalArgumentException  if the given ObjectName is null

     */

    public synchronized void enableObjectName(ObjectName objectName)

        throws IllegalArgumentException {

        if (objectName == null) {

            String excMsg = "Invalid parameter.";

            throw new IllegalArgumentException(excMsg);

        }

        RELATION_LOGGER.log(Level.TRACE, "ENTRY {0}", objectName);

        // Removes from deselected ObjectNames, if present

        if (deselectedNames != null) {

            if (deselectedNames.size() != 0) {

                deselectedNames.remove(objectName);

            }

        }

        // Adds it in selected ObjectNames

        if (selectedNames != null) {

            // If all are selected, no need to do anything :)

            if (!(selectedNames.contains(objectName))) {

                // ObjectName was not already selected

                selectedNames.add(objectName);

            }

        }

        RELATION_LOGGER.log(Level.TRACE, "RETURN");

        return;

    }

    /**

     * Gets all the ObjectNames enabled.

     *

     * @return Vector of ObjectNames:

     * <P>- null means all ObjectNames are implicitly selected, except the

     * ObjectNames explicitly deselected

     * <P>- empty means all ObjectNames are deselected, i.e. no ObjectName

     * selected.

     */

    public synchronized Vector<ObjectName> getEnabledObjectNames() {

        if (selectedNames != null) {

            return new Vector<ObjectName>(selectedNames);

        } else {

            return null;

        }

    }

    /**

     * Gets all the ObjectNames disabled.

     *

     * @return Vector of ObjectNames:

     * <P>- null means all ObjectNames are implicitly deselected, except the

     * ObjectNames explicitly selected

     * <P>- empty means all ObjectNames are selected, i.e. no ObjectName

     * deselected.

     */

    public synchronized Vector<ObjectName> getDisabledObjectNames() {

        if (deselectedNames != null) {

            return new Vector<ObjectName>(deselectedNames);

        } else {

            return null;

        }

    }

    //

    // NotificationFilter interface

    //

    /**

     * Invoked before sending the specified notification to the listener.

     * <P>If:

     * <P>- the ObjectName of the concerned MBean is selected (explicitly OR

     * (implicitly and not explicitly deselected))

     * <P>AND

     * <P>- the type of the operation (registration or unregistration) is

     * selected

     * <P>then the notification is sent to the listener.

     *

     * @param notif  The notification to be sent.

     *

     * @return true if the notification has to be sent to the listener, false

     * otherwise.

     *

     * @exception IllegalArgumentException  if null parameter

     */

    public synchronized boolean isNotificationEnabled(Notification notif)

        throws IllegalArgumentException {

        if (notif == null) {

            String excMsg = "Invalid parameter.";

            throw new IllegalArgumentException(excMsg);

        }

        RELATION_LOGGER.log(Level.TRACE, "ENTRY {0}", notif);

        // Checks the type first

        String ntfType = notif.getType();

        Vector<String> enabledTypes = getEnabledTypes();

        if (!(enabledTypes.contains(ntfType))) {

            RELATION_LOGGER.log(Level.TRACE,

                    "Type not selected, exiting");

            return false;

        }

        // We have a MBeanServerNotification: downcasts it

        MBeanServerNotification mbsNtf = (MBeanServerNotification)notif;

        // Checks the ObjectName

        ObjectName objName = mbsNtf.getMBeanName();

        // Is it selected?

        boolean isSelectedFlg = false;

        if (selectedNames != null) {

            // Not all are implicitly selected:

            // checks for explicit selection

            if (selectedNames.size() == 0) {

                // All are explicitly not selected

                RELATION_LOGGER.log(Level.TRACE,

                        "No ObjectNames selected, exiting");

                return false;

            }

            isSelectedFlg = selectedNames.contains(objName);

            if (!isSelectedFlg) {

                // Not in the explicit selected list

                RELATION_LOGGER.log(Level.TRACE,

                        "ObjectName not in selected list, exiting");

                return false;

            }

        }

        if (!isSelectedFlg) {

            // Not explicitly selected: is it deselected?

            if (deselectedNames == null) {

                // All are implicitly deselected and it is not explicitly

                // selected

                RELATION_LOGGER.log(Level.TRACE,

                        "ObjectName not selected, and all " +

                        "names deselected, exiting");

                return false;

            } else if (deselectedNames.contains(objName)) {

                // Explicitly deselected

                RELATION_LOGGER.log(Level.TRACE,

                        "ObjectName explicitly not selected, exiting");

                return false;

            }

        }

        RELATION_LOGGER.log(Level.TRACE,

                "ObjectName selected, exiting");

        return true;

    }

    /**

     * Deserializes an {@link MBeanServerNotificationFilter} from an {@link ObjectInputStream}.

     */

    private void readObject(ObjectInputStream in)

            throws IOException, ClassNotFoundException {

      if (compat)

      {

        // Read an object serialized in the old serial form

        //

        ObjectInputStream.GetField fields = in.readFields();

        selectedNames = cast(fields.get("mySelectObjNameList", null));

        if (fields.defaulted("mySelectObjNameList"))

        {

          throw new NullPointerException("mySelectObjNameList");

        }

        deselectedNames = cast(fields.get("myDeselectObjNameList", null));

        if (fields.defaulted("myDeselectObjNameList"))

        {

          throw new NullPointerException("myDeselectObjNameList");

        }

      }

      else

      {

        // Read an object serialized in the new serial form

        //

        in.defaultReadObject();

      }

    }

    /**

     * Serializes an {@link MBeanServerNotificationFilter} to an {@link ObjectOutputStream}.

     */

    private void writeObject(ObjectOutputStream out)

            throws IOException {

      if (compat)

      {

        // Serializes this instance in the old serial form

        //

        ObjectOutputStream.PutField fields = out.putFields();

        fields.put("mySelectObjNameList", selectedNames);

        fields.put("myDeselectObjNameList", deselectedNames);

        out.writeFields();

      }

      else

      {

        // Serializes this instance in the new serial form

        //

        out.defaultWriteObject();

      }

    }

}