org.opencms.cache.CmsVfsCache Maven / Gradle / Ivy
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/*
* This library is part of OpenCms -
* the Open Source Content Management System
*
* Copyright (c) Alkacon Software GmbH & Co. KG (http://www.alkacon.com)
*
* This library 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 2.1 of the License, or (at your option) any later version.
*
* This library 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.
*
* For further information about Alkacon Software, please see the
* company website: http://www.alkacon.com
*
* For further information about OpenCms, please see the
* project website: http://www.opencms.org
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
package org.opencms.cache;
import org.opencms.db.CmsDriverManager;
import org.opencms.file.CmsResource;
import org.opencms.main.CmsEvent;
import org.opencms.main.I_CmsEventListener;
import org.opencms.main.OpenCms;
import org.opencms.util.CmsCollectionsGenericWrapper;
import java.util.List;
/**
* Configurable VFS based cache, for caching objects related to offline/online resources.
*
* @since 7.6
*/
public abstract class CmsVfsCache implements I_CmsEventListener {
/**
* Initializes the cache. Only intended to be called during startup.
*/
protected CmsVfsCache() {
// empty
}
/**
* @see org.opencms.main.I_CmsEventListener#cmsEvent(org.opencms.main.CmsEvent)
*/
public void cmsEvent(CmsEvent event) {
CmsResource resource = null;
List resources = null;
switch (event.getType()) {
case I_CmsEventListener.EVENT_RESOURCE_AND_PROPERTIES_MODIFIED:
case I_CmsEventListener.EVENT_RESOURCE_MODIFIED:
Object change = event.getData().get(I_CmsEventListener.KEY_CHANGE);
if ((change != null) && change.equals(new Integer(CmsDriverManager.NOTHING_CHANGED))) {
// skip lock & unlock
return;
}
// a resource has been modified in a way that it *IS NOT* necessary also to clear
// lists of cached sub-resources where the specified resource might be contained inside.
resource = (CmsResource)event.getData().get(I_CmsEventListener.KEY_RESOURCE);
uncacheResource(resource);
break;
case I_CmsEventListener.EVENT_RESOURCES_AND_PROPERTIES_MODIFIED:
// a list of resources and all of their properties have been modified
resources = CmsCollectionsGenericWrapper.list(event.getData().get(I_CmsEventListener.KEY_RESOURCES));
uncacheResources(resources);
break;
case I_CmsEventListener.EVENT_RESOURCE_MOVED:
case I_CmsEventListener.EVENT_RESOURCE_DELETED:
case I_CmsEventListener.EVENT_RESOURCES_MODIFIED:
// a list of resources has been modified
resources = CmsCollectionsGenericWrapper.list(event.getData().get(I_CmsEventListener.KEY_RESOURCES));
uncacheResources(resources);
break;
case I_CmsEventListener.EVENT_CLEAR_ONLINE_CACHES:
case I_CmsEventListener.EVENT_PUBLISH_PROJECT:
flush(true);
break;
case I_CmsEventListener.EVENT_CLEAR_CACHES:
flush(true);
flush(false);
break;
case I_CmsEventListener.EVENT_CLEAR_OFFLINE_CACHES:
flush(false);
break;
default:
// noop
break;
}
}
/**
* Clean up at shutdown time. Only intended to be called at system shutdown.
*
* @see org.opencms.main.OpenCmsCore#shutDown
*/
public void shutdown() {
if (OpenCms.getMemoryMonitor() != null) {
// prevent accidental calls
return;
}
flush(true);
flush(false);
}
/**
* Flushes the caches.
*
* @param online if to flush the online or offline caches
*/
protected abstract void flush(boolean online);
/**
* Adds this instance as an event listener to the CMS event manager.
*/
protected void registerEventListener() {
OpenCms.addCmsEventListener(
this,
new int[] {
I_CmsEventListener.EVENT_RESOURCE_AND_PROPERTIES_MODIFIED,
I_CmsEventListener.EVENT_RESOURCES_AND_PROPERTIES_MODIFIED,
I_CmsEventListener.EVENT_RESOURCE_MODIFIED,
I_CmsEventListener.EVENT_RESOURCES_MODIFIED,
I_CmsEventListener.EVENT_RESOURCE_MOVED,
I_CmsEventListener.EVENT_RESOURCE_DELETED,
I_CmsEventListener.EVENT_PUBLISH_PROJECT,
I_CmsEventListener.EVENT_CLEAR_CACHES,
I_CmsEventListener.EVENT_CLEAR_ONLINE_CACHES,
I_CmsEventListener.EVENT_CLEAR_OFFLINE_CACHES});
}
/**
* Removes a cached resource from the cache.
*
* @param resource the resource
*/
protected abstract void uncacheResource(CmsResource resource);
/**
* Removes a bunch of cached resources from the cache.
*
* @param resources a list of resources
*
* @see #uncacheResource(CmsResource)
*/
protected void uncacheResources(List resources) {
if (resources == null) {
return;
}
for (int i = 0, n = resources.size(); i < n; i++) {
// remove the resource
uncacheResource(resources.get(i));
}
}
}