/**
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.apache.solr.search;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import java.util.Map;
import org.apache.solr.common.SolrException;
import org.apache.solr.common.util.DOMUtil;
import org.apache.solr.core.SolrConfig;
import org.apache.solr.core.SolrResourceLoader;
import javax.xml.xpath.XPathConstants;
/**
* Contains the knowledge of how cache config is
* stored in the solrconfig.xml file, and implements a
* factory to create caches.
*
* @version $Id: CacheConfig.java 818808 2009-09-25 10:24:58Z shalin $
*/
public class CacheConfig {
private String nodeName;
private Class clazz;
private Map<String,String> args;
private CacheRegenerator regenerator;
private String cacheImpl;
private Object[] persistence = new Object[1];
private String regenImpl;
public CacheConfig() {}
public CacheConfig(Class clazz, Map<String,String> args, CacheRegenerator regenerator) {
this.clazz = clazz;
this.args = args;
this.regenerator = regenerator;
}
public CacheRegenerator getRegenerator() {
return regenerator;
}
public void setRegenerator(CacheRegenerator regenerator) {
this.regenerator = regenerator;
}
public static CacheConfig[] getMultipleConfigs(SolrConfig solrConfig, String configPath) {
NodeList nodes = (NodeList)solrConfig.evaluate(configPath, XPathConstants.NODESET);
if (nodes==null || nodes.getLength()==0) return null;
CacheConfig[] configs = new CacheConfig[nodes.getLength()];
for (int i=0; i<nodes.getLength(); i++) {
configs[i] = getConfig(solrConfig, nodes.item(i));
}
return configs;
}
public static CacheConfig getConfig(SolrConfig solrConfig, String xpath) {
Node node = solrConfig.getNode(xpath, false);
return getConfig(solrConfig, node);
}
public static CacheConfig getConfig(SolrConfig solrConfig, Node node) {
if (node==null) return null;
CacheConfig config = new CacheConfig();
config.nodeName = node.getNodeName();
config.args = DOMUtil.toMap(node.getAttributes());
String nameAttr = config.args.get("name"); // OPTIONAL
if (nameAttr==null) {
config.args.put("name",config.nodeName);
}
SolrResourceLoader loader = solrConfig.getResourceLoader();
config.cacheImpl = config.args.get("class");
config.regenImpl = config.args.get("regenerator");
config.clazz = loader.findClass(config.cacheImpl);
if (config.regenImpl != null) {
config.regenerator = (CacheRegenerator) loader.newInstance(config.regenImpl);
}
return config;
}
public SolrCache newInstance() {
try {
SolrCache cache = (SolrCache)clazz.newInstance();
persistence[0] = cache.init(args, persistence[0], regenerator);
return cache;
} catch (Exception e) {
SolrException.log(SolrCache.log,"Error instantiating cache",e);
// we can carry on without a cache... but should we?
// in some cases (like an OOM) we probably should try to continue.
return null;
}
}
}