/*
* JBoss, the OpenSource J2EE webOS
*
* Distributable under LGPL license.
* See terms of license at gnu.org.
*/
package org.jboss.cache.eviction;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.jboss.cache.ConfigureException;
import org.jboss.cache.xml.XmlHelper;
import org.w3c.dom.Element;
/**
* LFU Configuration implementation for LFU Policy.
*
* @author Daniel Huang (dhuang@jboss.org)
* @version $Revision: 1852 $
*/
public class LFUConfiguration implements EvictionConfiguration
{
private static final Log log = LogFactory.getLog(LFUConfiguration.class);
private int minNodes;
private int maxNodes;
public int getMinNodes()
{
return minNodes;
}
public void setMinNodes(int minNodes)
{
this.minNodes = minNodes;
}
public int getMaxNodes()
{
return maxNodes;
}
public void setMaxNodes(int maxNodes)
{
this.maxNodes = maxNodes;
}
/**
* Configures the LFU Policy with XML.
* <p/>
* This method expects the following XML DOM:
* <p/>
* <region name="abc">
* <attribute name="minNodes">10</attribute>
* <attribute name="maxNodes">20</attribute>
* </region>
*
* @param element XML DOM object containing LFU configuration.
* @throws ConfigureException
*/
public void parseXMLConfig(Element element) throws ConfigureException
{
String name = element.getAttribute(EvictionConfiguration.NAME);
if (name == null || name.equals(""))
{
throw new ConfigureException("Name is required for the eviction region");
}
String maxNodes = XmlHelper.getAttr(element,
EvictionConfiguration.MAX_NODES, EvictionConfiguration.ATTR, EvictionConfiguration.NAME);
if (maxNodes != null)
{
setMaxNodes(Integer.parseInt(maxNodes));
}
else
{
setMaxNodes(0);
}
String minNodes = XmlHelper.getAttr(element, EvictionConfiguration.MIN_NODES,
EvictionConfiguration.ATTR, EvictionConfiguration.NAME);
if (minNodes != null)
{
setMinNodes(Integer.parseInt(minNodes));
}
else
{
setMinNodes(0);
}
if (log.isDebugEnabled())
{
log.debug("parseConfig: name -- " + name + " maxNodes -- "
+ getMaxNodes() + " minNodes -- " + getMinNodes());
}
}
public String toString()
{
StringBuffer ret = new StringBuffer();
ret.append("LFUConfiguration: maxNodes = ").append(getMaxNodes()).append(" minNodes = ").append(getMinNodes());
return ret.toString();
}
}