log4j实例,详细使用配置和编码

package org.cjj.config; import java.io.FileNotFoundException; import java.io.IOException; import java.io.InputStream; import java.net.URL; import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory; import javax.xml.parsers.FactoryConfigurationError; import javax.xml.parsers.ParserConfigurationException; import org.apache.log4j.xml.DOMConfigurator; import org.w3c.dom.Document; import org.w3c.dom.Element; import org.xml.sax.SAXException; public class Log4jConfigurator { private Log4jConfigurator() { } /** * @param is * @throws FactoryConfigurationError */ public static boolean configure(final InputStream is) throws FactoryConfigurationError { final DocumentBuilderFactory domfac = DocumentBuilderFactory.newInstance(); try { domfac.setValidating(false); final DocumentBuilder dombuilder = domfac.newDocumentBuilder(); dombuilder.setEntityResolver(IgnoreDTDEntityResolver.getInstance()); final Document doc = dombuilder.parse(is); final Element root = doc.getDocumentElement(); DOMConfigurator.configure(root); // 装载Log4j配置文件 return true; } catch (final ParserConfigurationException e) { e.printStackTrace(); } catch (final FileNotFoundException e) { e.printStackTrace(); } catch (final SAXException e) { e.printStackTrace(); } catch (final IOException e) { e.printStackTrace(); } return false; } public static void configure(final Element element) throws FactoryConfigurationError { DOMConfigurator.configure(element); } public static void configure(final String filename) throws FactoryConfigurationError { DOMConfigurator.configure(filename); } public static void configure(final URL url) throws FactoryConfigurationError { DOMConfigurator.configure(url); } }