001/*
002 * The contents of this file are subject to the terms of the Common Development and
003 * Distribution License (the License). You may not use this file except in compliance with the
004 * License.
005 *
006 * You can obtain a copy of the License at legal/CDDLv1.0.txt. See the License for the
007 * specific language governing permission and limitations under the License.
008 *
009 * When distributing Covered Software, include this CDDL Header Notice in each file and include
010 * the License file at legal/CDDLv1.0.txt. If applicable, add the following below the CDDL
011 * Header, with the fields enclosed by brackets [] replaced by your own identifying
012 * information: "Portions Copyright [year] [name of copyright owner]".
013 *
014 * Copyright 2008 Sun Microsystems, Inc.
015 * Portions Copyright 2016 ForgeRock AS.
016 */
017package org.forgerock.opendj.config.server;
018
019import java.util.Collection;
020
021import org.forgerock.i18n.LocalizableMessage;
022
023/**
024 * An interface for performing server-side constraint validation.
025 * <p>
026 * Constraints are evaluated immediately before and after write operations are
027 * performed. Server-side constraints are evaluated in two phases: the first
028 * phase determines if the proposed add, delete, or modification is acceptable
029 * according to the constraint. If one or more constraints fails, the write
030 * write operation is refused, and the client will receive an
031 * <code>OperationRejectedException</code> exception. The second phase is
032 * invoked once the add, delete, or modification request has been allowed and
033 * any changes applied. The second phase gives the constraint handler a chance
034 * to register listener call-backs if required.
035 * <p>
036 * A server constraint handler must override at least one of the provided
037 * methods.
038 *
039 * @see org.forgerock.opendj.config.Constraint
040 */
041public abstract class ServerConstraintHandler {
042
043    /** Creates a new server constraint handler. */
044    protected ServerConstraintHandler() {
045        // No implementation required.
046    }
047
048    /**
049     * Determines whether the existing managed object can be deleted from
050     * the server's configuration. For example, an implementation might enforce
051     * referential integrity by preventing referenced managed objects from being
052     * deleted.
053     * <p>
054     * If the constraint is not satisfied, the implementation must return
055     * <code>false</code> and add a message describing why the managed object
056     * cannot be deleted.
057     * <p>
058     * The default implementation is to return <code>true</code>.
059     *
060     * @param managedObject
061     *            The managed object which is about to be deleted.
062     * @param unacceptableReasons
063     *            A list of messages to which error messages should be added.
064     * @return Returns <code>true</code> if this constraint is satisfied, or
065     *         <code>false</code> if it is not and the managed object cannot be
066     *         deleted.
067     * @throws ConfigException
068     *             If an configuration exception prevented this constraint from
069     *             being evaluated.
070     */
071    public boolean isDeleteAllowed(ServerManagedObject<?> managedObject,
072            Collection<LocalizableMessage> unacceptableReasons) throws ConfigException {
073        return true;
074    }
075
076    /**
077     * Determines whether the provided managed object can be used by the
078     * server. This method is invoked each time a managed object is decoded by
079     * the administration framework: when an attempt is made to add a new
080     * configuration, modify an existing configuration, or during server
081     * initialization. If the constraint is not satisfied the managed object
082     * will be rejected.
083     * <p>
084     * If the constraint is not satisfied, the implementation must return
085     * <code>false</code> and add a message describing why the managed object is
086     * not usable.
087     * <p>
088     * The default implementation is to return <code>true</code>.
089     *
090     * @param managedObject
091     *            The new managed object.
092     * @param unacceptableReasons
093     *            A list of messages to which error messages should be added.
094     * @return Returns <code>true</code> if this constraint is satisfied, or
095     *         <code>false</code> if it is not and the managed object cannot be
096     *         used.
097     * @throws ConfigException
098     *             If an configuration exception prevented this constraint from
099     *             being evaluated.
100     */
101    public boolean isUsable(ServerManagedObject<?> managedObject, Collection<LocalizableMessage> unacceptableReasons)
102            throws ConfigException {
103        return true;
104    }
105
106    /**
107     * Performs any post-add processing required by this constraint. This method
108     * is invoked after a new managed object has been accepted for use by the
109     * administration framework. This might occur during initialization or when
110     * a managed object is added at run-time.
111     * <p>
112     * The default implementation is to do nothing.
113     *
114     * @param managedObject
115     *            The managed object which has just been added to the server's
116     *            configuration.
117     * @throws ConfigException
118     *             If the post-add processing fails due to a configuration
119     *             exception.
120     */
121    public void performPostAdd(ServerManagedObject<?> managedObject) throws ConfigException {
122        // Do nothing.
123    }
124
125    /**
126     * Performs any post-delete processing required by this constraint. This
127     * method is invoked after a managed object has been accepted for deletion
128     * from the server's configuration.
129     * <p>
130     * The default implementation is to do nothing.
131     *
132     * @param managedObject
133     *            The managed object which was deleted.
134     * @throws ConfigException
135     *             If the post-delete processing fails due to a configuration
136     *             exception.
137     */
138    public void performPostDelete(ServerManagedObject<?> managedObject) throws ConfigException {
139        // Do nothing.
140    }
141
142    /**
143     * Performs any post-modify processing required by this constraint. This
144     * method is invoked after changes to an existing managed object have been
145     * accepted.
146     * <p>
147     * The default implementation is to do nothing.
148     *
149     * @param managedObject
150     *            The managed object which was modified.
151     * @throws ConfigException
152     *             If the post-modify processing fails due to a configuration
153     *             exception.
154     */
155    public void performPostModify(ServerManagedObject<?> managedObject) throws ConfigException {
156        // Do nothing.
157    }
158}