PreDeliveryPlugin.java

/**
 * Copyright (c) Codice Foundation
 * <p>
 * This is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser
 * General Public License as published by the Free Software Foundation, either version 3 of the
 * License, or any later version.
 * <p>
 * This program 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
 * Lesser General Public License for more details. A copy of the GNU Lesser General Public License
 * is distributed along with this program and can be found at
 * <http://www.gnu.org/licenses/lgpl.html>.
 */
package ddf.catalog.plugin;

import ddf.catalog.data.Metacard;
import ddf.catalog.operation.Update;

/**
 * The PreDeliveryPlugin is executed prior to an event being delivered.
 *
 * @author michael.menousek@lmco.com
 *
 */
public interface PreDeliveryPlugin {

    /**
     * Callback invoked when a {@link Metacard} has created
     *
     * @param metacard
     *            - the newly created {@link Metacard}
     * @return the value of the {@link Metacard} to pass to the next {@link PreDeliveryPlugin}, or
     *         if this is the last {@link PreDeliveryPlugin} to be called, the
     *         {@link ddf.catalog.event.DeliveryMethod}
     * @throws PluginExecutionException
     *             if there is a problem evaluating the update but processing should continue
     * @throws StopProcessingException
     *             if this Catalog Plugin will not allow the current notification to occur
     */
    public Metacard processCreate(Metacard metacard)
            throws PluginExecutionException, StopProcessingException;

    /**
     * Callback invoked when a {@link Metacard} has been updated and only the old version matches a
     * {@link ddf.catalog.event.Subscription}
     *
     * @param update
     * @return the {@link Update} to pass to the next {@link PreDeliveryPlugin}, or if this is the
     *         last {@link PreDeliveryPlugin} to be called, the {@link ddf.catalog.event.DeliveryMethod}
     * @throws PluginExecutionException
     *             if there is a problem evaluating the update but processing should continue
     * @throws StopProcessingException
     *             if this Catalog Plugin will not allow the current notification to occur
     *
     */
    public Update processUpdateMiss(Update update)
            throws PluginExecutionException, StopProcessingException;

    /**
     * Callback invoked when a {@link Metacard} has been updated and the new version matches a
     * {@link ddf.catalog.event.Subscription}. The old version may or may not match the {@link ddf.catalog.event.Subscription}
     *
     * @param update
     * @return the {@link Update} to pass to the next {@link PreDeliveryPlugin}, or if this is the
     *         last {@link PreDeliveryPlugin} to be called, the {@link ddf.catalog.event.DeliveryMethod}
     * @throws PluginExecutionException
     *             if there is a problem evaluating the update but processing should continue
     * @throws StopProcessingException
     *             if this Catalog Plugin will not allow the current notification to occur
     */
    public Update processUpdateHit(Update update)
            throws PluginExecutionException, StopProcessingException;

    /**
     * Callback invoked when a {@link Metacard} has been deleted
     *
     * @param metacard
     *            - the deleted {@link Metacard}
     * @return the {@link Metacard} to pass to the next {@link PreDeliveryPlugin}, or if this is the
     *         last {@link PreDeliveryPlugin} to be called, the {@link ddf.catalog.event.DeliveryMethod}
     * @throws PluginExecutionException
     *             if there is a problem evaluating the update but processing should continue
     * @throws StopProcessingException
     *             if this Catalog Plugin will not allow the current notification to occur
     */
    public Metacard processDelete(Metacard metacard)
            throws PluginExecutionException, StopProcessingException;
}