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* Copyright 2000 - 2008, Red Hat Middleware LLC, and individual contributors
* as indicated by the @author tags. See the copyright.txt file in the
* distribution for a full listing of individual contributors.
*
* 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 2.1 of
* the License, or (at your option) any later version.
*
* This software 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.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.jboss.cache.config.parsing.element;
import org.jboss.cache.config.ConfigurationException;
import org.jboss.cache.config.EvictionAlgorithmConfig;
import org.jboss.cache.config.EvictionConfig;
import org.jboss.cache.config.EvictionRegionConfig;
import org.jboss.cache.config.MissingPolicyException;
import org.jboss.cache.config.parsing.XmlConfigHelper;
import org.jboss.cache.config.parsing.XmlParserBase;
import org.jboss.cache.config.parsing.RootElementBuilder;
import org.jboss.cache.eviction.EvictionAlgorithm;
import org.jboss.cache.util.Util;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;
import java.util.LinkedList;
import java.util.List;
import java.util.Properties;
/**
* Knows how to parse the <b>eviction</b> xml element.
* <pre>
* Note: class does not rely on element position in the configuration file.
* It does not rely on element's name either.
* </pre>
*
* @author Mircea.Markus@jboss.com
* @since 3.0
*/
public class EvictionElementParser extends XmlParserBase
{
public EvictionElementParser()
{
this(RootElementBuilder.DEFAULT_CORE_NS);
}
public EvictionElementParser(String coreNamespace)
{
this.coreNamespace = coreNamespace;
}
public EvictionConfig parseEvictionElement(Element evictionElement)
{
assertNotLegacyElement(evictionElement);
EvictionConfig evictionConfig = new EvictionConfig();
String wakeUpInterval = getAttributeValue(evictionElement, "wakeUpInterval");
if (existsAttribute(wakeUpInterval))
{
evictionConfig.setWakeupInterval(getInt(wakeUpInterval));
}
else
{
throw new ConfigurationException("Missing mandatory attribute wakeUpInterval");
}
List<EvictionRegionConfig> evictionRegionConfigs = new LinkedList<EvictionRegionConfig>();
Element defaultRegion = getSingleElementInCoreNS("default", evictionElement);
if (defaultRegion != null)
{
EvictionRegionConfig defaultRegionConfig = getEvictionRegionConfig(defaultRegion, null, true);
if (defaultRegionConfig.getEvictionAlgorithmConfig() == null)
throw new MissingPolicyException("Default eviction region should have an evictionAlgorithmClass defined.");
evictionConfig.setDefaultEvictionRegionConfig(defaultRegionConfig);
}
NodeList regions = evictionElement.getElementsByTagName("region");
for (int i = 0; i < regions.getLength(); i++)
{
Element regionConfig = (Element) regions.item(i);
EvictionRegionConfig erc = getEvictionRegionConfig(regionConfig, evictionConfig.getDefaultEvictionRegionConfig(), false);
evictionConfig.applyDefaults(erc);
evictionRegionConfigs.add(erc);
}
evictionConfig.setEvictionRegionConfigs(evictionRegionConfigs);
return evictionConfig;
}
@SuppressWarnings("unchecked")
private EvictionRegionConfig getEvictionRegionConfig(Element element, EvictionRegionConfig defaultRegion, boolean isDefault)
{
EvictionRegionConfig erc = new EvictionRegionConfig();
erc.setRegionName(getAttributeValue(element, "name"));
String queueSize = getAttributeValue(element, "eventQueueSize");
if (existsAttribute(queueSize))
{
erc.setEventQueueSize(getInt(queueSize));
}
else if (defaultRegion == null)
{
erc.setEventQueueSize(EvictionConfig.EVENT_QUEUE_SIZE_DEFAULT);
}
String algorithmClassName = getAttributeValue(element, "algorithmClass");
EvictionAlgorithmConfig algorithmConfig = null; // every eviction region config needs an algorithm config.
if (existsAttribute(algorithmClassName))
{
EvictionAlgorithm algorithm;
Class<? extends EvictionAlgorithm> algorithmClass;
// try using a 'getInstance()' factory.
try
{
algorithmClass = Util.loadClass(algorithmClassName);
}
catch (Exception e)
{
throw new RuntimeException("Unable to load eviction algorithm class [" + algorithmClassName + "]", e);
}
try
{
algorithm = Util.getInstance(algorithmClass);
}
catch (Exception e)
{
throw new ConfigurationException("Unable to construct eviction algorithm class [" + algorithmClassName + "]", e);
}
try
{
algorithmConfig = Util.getInstance(algorithm.getConfigurationClass());
}
catch (Exception e)
{
throw new RuntimeException("Failed to instantiate eviction algorithm configuration class [" +
algorithm.getConfigurationClass() + "]", e);
}
}
else
{
if (!isDefault)
{
if (defaultRegion == null || defaultRegion.getEvictionAlgorithmConfig() == null)
{
throw new MissingPolicyException("There is no Eviction Algorithm Class specified on the region or for the entire cache!");
}
else
{
try
{
algorithmConfig = defaultRegion.getEvictionAlgorithmConfig().clone();
}
catch (CloneNotSupportedException e)
{
throw new ConfigurationException("Unable to clone eviction algorithm configuration from default", e);
}
}
}
}
if (algorithmConfig != null)
{
parseEvictionPolicyConfig(element, algorithmConfig);
erc.setEvictionAlgorithmConfig(algorithmConfig);
}
String actionPolicyClass = getAttributeValue(element, "actionPolicyClass");
if (existsAttribute(actionPolicyClass))
{
erc.setEvictionActionPolicyClassName(actionPolicyClass);
}
else if (defaultRegion == null)
{
// this is the default region. Make sure we set the default EvictionActionPolicyClass.
erc.setEvictionActionPolicyClassName(EvictionConfig.EVICTION_ACTION_POLICY_CLASS_DEFAULT);
}
return erc;
}
public static void parseEvictionPolicyConfig(Element element, EvictionAlgorithmConfig target)
{
// target.reset();
Properties p = XmlConfigHelper.extractProperties(element);
XmlConfigHelper.setValues(target, p, false, true);
}
}