Java tutorial
/* * JBoss, Home of Professional Open Source * Copyright 2005, JBoss Inc., and individual contributors as indicated * by the @authors tag. See the copyright.txt 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.jbpm.instantiation; import java.lang.reflect.Constructor; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.dom4j.DocumentException; import org.dom4j.DocumentHelper; import org.dom4j.Element; import org.jbpm.JbpmException; public class XmlInstantiator implements Instantiator { private static final Class[] parameterTypes = new Class[] { Element.class }; public Object instantiate(Class clazz, String configuration) { Object newInstance = null; try { // parse the bean configuration Element configurationElement = parseConfiguration(configuration); Constructor constructor = clazz.getDeclaredConstructor(parameterTypes); constructor.setAccessible(true); newInstance = constructor.newInstance(new Object[] { configurationElement }); } catch (Exception e) { log.error("couldn't instantiate '" + clazz.getName() + "'", e); throw new JbpmException(e); } return newInstance; } protected Element parseConfiguration(String configuration) { Element element = null; try { element = DocumentHelper.parseText("<action>" + configuration + "</action>").getRootElement(); } catch (DocumentException e) { log.error("couldn't parse bean configuration : " + configuration, e); throw new JbpmException(e); } return element; } private static final Log log = LogFactory.getLog(XmlInstantiator.class); }