Java tutorial
/** * License Agreement for OpenSearchServer * * Copyright (C) 2011-2012 Emmanuel Keller / Jaeksoft * * http://www.open-search-server.com * * This file is part of OpenSearchServer. * * 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. * * 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. * * 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.renderer; import java.io.File; import java.io.IOException; import java.util.Map; import java.util.TreeMap; import javax.xml.parsers.ParserConfigurationException; import javax.xml.xpath.XPathExpressionException; import org.apache.commons.io.FilenameUtils; import org.xml.sax.SAXException; import com.jaeksoft.searchlib.SearchLibException; import com.jaeksoft.searchlib.config.Config; import com.jaeksoft.searchlib.util.ReadWriteLock; import com.jaeksoft.searchlib.util.XPathParser; public class RendererManager { private final ReadWriteLock rwl = new ReadWriteLock(); private Renderer[] array; private TreeMap<String, Renderer> map; public RendererManager(Config config, File directory) throws SearchLibException, XPathExpressionException, ParserConfigurationException, SAXException, IOException { array = null; map = new TreeMap<String, Renderer>(); for (File f : directory.listFiles()) { if (f.isFile()) { String fname = f.getName(); if (!FilenameUtils.isExtension(fname, "xml")) continue; if (fname.endsWith("_old.xml")) continue; if (fname.endsWith("_tmp.xml")) continue; if (f.exists()) add(new Renderer(new XPathParser(f))); else add(new Renderer()); } } } private void buildArray() { array = new Renderer[map.size()]; int i = 0; for (Map.Entry<String, Renderer> entry : map.entrySet()) array[i++] = entry.getValue(); } public Renderer[] getArray() { rwl.r.lock(); try { return array; } finally { rwl.r.unlock(); } } public void add(Renderer item) throws SearchLibException { rwl.w.lock(); try { if (map.containsKey(item.getName())) throw new SearchLibException("This item already exists"); map.put(item.getName(), item); buildArray(); } finally { rwl.w.unlock(); } } public Renderer get(String rendererName) { rwl.r.lock(); try { return map.get(rendererName); } finally { rwl.r.unlock(); } } public void replace(Renderer oldItem, Renderer newItem) { rwl.w.lock(); try { map.remove(oldItem.getName()); map.put(newItem.getName(), newItem); buildArray(); } finally { rwl.w.unlock(); } } public void remove(Renderer item) { rwl.w.lock(); try { map.remove(item.getName()); buildArray(); } finally { rwl.w.unlock(); } } }