DatabaseCrawlList.java

/**
 * License Agreement for OpenSearchServer
 * <p>
 * Copyright (C) 2010-2016 Emmanuel Keller / Jaeksoft
 * <p>
 * http://www.open-search-server.com
 * <p>
 * This file is part of OpenSearchServer.
 * <p>
 * OpenSearchServer is free software: you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 * <p>
 * OpenSearchServer 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 General Public License for more details.
 * <p>
 * You should have received a copy of the GNU General Public License
 * along with OpenSearchServer.
 * If not, see <http://www.gnu.org/licenses/>.
 **/

package com.jaeksoft.searchlib.crawler.database;

import java.io.File;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.util.TreeMap;

import javax.xml.parsers.ParserConfigurationException;
import javax.xml.xpath.XPathExpressionException;

import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.SAXException;

import com.jaeksoft.searchlib.util.ReadWriteLock;
import com.jaeksoft.searchlib.util.XPathParser;
import com.jaeksoft.searchlib.util.XmlWriter;

public class DatabaseCrawlList implements XmlWriter.Interface {

	final private ReadWriteLock rwl = new ReadWriteLock();

	private TreeMap<String, DatabaseCrawlAbstract> map;
	private DatabaseCrawlAbstract[] array;

	private DatabaseCrawlList() {
		map = new TreeMap<String, DatabaseCrawlAbstract>();
	}

	private final static String DBCRAWLLIST_ROOTNODE_NAME = "databaseCrawlList";

	public static DatabaseCrawlList fromXml(DatabaseCrawlMaster crawlMaster, DatabasePropertyManager propertyManager,
			File file) throws XPathExpressionException, ParserConfigurationException, SAXException, IOException {
		DatabaseCrawlList dbCrawlList = new DatabaseCrawlList();
		if (!file.exists())
			return dbCrawlList;
		XPathParser xpp = new XPathParser(file);
		Node rootNode = xpp.getNode(DBCRAWLLIST_ROOTNODE_NAME);
		if (rootNode == null)
			return dbCrawlList;
		NodeList nodes = xpp.getNodeList(rootNode, DatabaseCrawlAbstract.DBCRAWL_NODE_NAME);
		if (nodes == null)
			return dbCrawlList;
		for (int i = 0; i < nodes.getLength(); i++) {
			Node crawlNode = nodes.item(i);
			DatabaseCrawlEnum type = DatabaseCrawlEnum
					.find(XPathParser.getAttributeString(crawlNode, DatabaseCrawlAbstract.DBCRAWL_ATTR_TYPE));
			DatabaseCrawlAbstract dbCrawl = null;
			switch (type) {
			case DB_SQL:
				dbCrawl = new DatabaseCrawlSql(crawlMaster, propertyManager, xpp, nodes.item(i));
				break;
			case DB_MONGO_DB:
				dbCrawl = new DatabaseCrawlMongoDb(crawlMaster, propertyManager, xpp, nodes.item(i));
				break;
			}
			if (dbCrawl != null)
				dbCrawlList.add(dbCrawl);
		}
		return dbCrawlList;
	}

	public void add(DatabaseCrawlAbstract dbCrawl) {
		rwl.w.lock();
		try {
			map.put(dbCrawl.getName(), dbCrawl);
			buildArray();
		} finally {
			rwl.w.unlock();
		}
	}

	public DatabaseCrawlAbstract get(String name) {
		rwl.r.lock();
		try {
			return map.get(name);
		} finally {
			rwl.r.unlock();
		}
	}

	public void remove(DatabaseCrawlAbstract dbCrawl) {
		rwl.w.lock();
		try {
			map.remove(dbCrawl.getName());
			buildArray();
		} finally {
			rwl.w.unlock();
		}
	}

	@Override
	public void writeXml(XmlWriter xmlWriter) throws SAXException, UnsupportedEncodingException {
		rwl.r.lock();
		try {
			xmlWriter.startElement(DBCRAWLLIST_ROOTNODE_NAME);
			for (DatabaseCrawlAbstract item : map.values())
				item.writeXml(xmlWriter);
			xmlWriter.endElement();
		} finally {
			rwl.r.unlock();
		}
	}

	private void buildArray() {
		array = new DatabaseCrawlAbstract[map.size()];
		map.values().toArray(array);
	}

	public DatabaseCrawlAbstract[] getArray() {
		rwl.r.lock();
		try {
			return array;
		} finally {
			rwl.r.unlock();
		}
	}

}