/*
* Autopsy Forensic Browser
*
* Copyright 2011-2016 Basis Technology Corp.
* Contact: carrier <at> sleuthkit <dot> org
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.sleuthkit.autopsy.ingest.events;
import java.io.Serializable;
import java.util.logging.Level;
import org.sleuthkit.autopsy.casemodule.Case;
import org.sleuthkit.autopsy.coreutils.Logger;
import org.sleuthkit.autopsy.events.AutopsyEvent;
import org.sleuthkit.autopsy.ingest.IngestManager;
import org.sleuthkit.autopsy.ingest.ModuleContentEvent;
import org.sleuthkit.datamodel.Content;
import org.sleuthkit.datamodel.TskCoreException;
/**
* Event published when new content is added to a case or there is a change a
* recorded attribute of existing content. For example, a content changed event
* should be published when an analysis (ingest) module adds an extracted or
* carved file to a case. The "old" value is a legacy ModuleContentEvent object.
* The "new" value is null.
*/
public final class ContentChangedEvent extends AutopsyEvent implements Serializable {
private static final long serialVersionUID = 1L;
private static final Logger logger = Logger.getLogger(ContentChangedEvent.class.getName());
private transient ModuleContentEvent eventData;
/**
* Constructs a event to be published when new content is added to a case or
* there is a change a recorded attribute of existing content.
*
* @param eventData A ModuleContentEvent object containing the data
* associated with the content addition or change.
*/
public ContentChangedEvent(ModuleContentEvent eventData) {
/**
* Putting a serializable data holding object into newValue to allow for
* lazy loading of the ModuleContent object. This bypasses the issues
* related to the serialization and de-serialization of Content objects
* when the event is published over a network.
*/
super(
IngestManager.IngestModuleEvent.CONTENT_CHANGED.toString(),
new SerializableEventData(eventData.getModuleName(), ((Content) eventData.getSource()).getId()),
null
);
}
/**
* Gets the legacy ModuleContentEvent object associated with this event.
* Note that the content object that was added or changed can be accessed
* via the getSource() method of the ModuleContentEvent.
*
* @return The ModuleContentEvent.
*/
@Override
public Object getOldValue() {
/**
* The eventData field is set in the constructor, but it is transient so
* it will become null when the event is serialized for publication over
* a network. Doing a lazy load of the ModuleContentEvent object
* bypasses the issues related to the serialization and de-serialization
* of Content objects and may also save database round trips from other
* nodes since subscribers to this event are often not interested in the
* event data.
*/
if (null != eventData) {
return eventData;
}
try {
SerializableEventData data = (SerializableEventData) super.getOldValue();
Content content = Case.getCurrentCase().getSleuthkitCase().getContentById(data.contentId);
eventData = new ModuleContentEvent(data.moduleName, content);
return eventData;
} catch (IllegalStateException | TskCoreException ex) {
logger.log(Level.SEVERE, "Error doing lazy load for remote event", ex); //NON-NLS
return null;
}
}
/**
* Data holder class.
*/
private static final class SerializableEventData implements Serializable {
private static final long serialVersionUID = 1L;
private final String moduleName;
private final long contentId;
private SerializableEventData(String moduleName, long contentId) {
this.moduleName = moduleName;
this.contentId = contentId;
}
}
}