1 建立log.properties

　　log level定为INFO，不显示DEBUG信息。log输出依次为文件，控制台

　　log4j.rootLogger=INFO,R,CONSOLE#DEBUG,CONSOLElog4j.addivity.org.apache=true #################### Console Appender###################log4j.appender.CONSOLE=org.apache.log4j.ConsoleAppenderlog4j.appender.Threshold=DEBUGlog4j.appender.CONSOLE.Target=System.outlog4j.appender.CONSOLE.layout=org.apache.log4j.PatternLayoutlog4j.appender.CONSOLE.layout.ConversionPattern=[framework] %d - %c -%-4r [%t] %-5p %c %x - %m%n###################### File Appender，文件满100kb，自动生成file.log.n#####################log4j.appender.R=org.apache.log4j.RollingFileAppenderlog4j.appender.R.File=d:\\file.loglog4j.appender.R.MaxFileSize=100KB# Keep one backup filelog4j.appender.R.MaxBackupIndex=1log4j.appender.R.layout=org.apache.log4j.PatternLayoutlog4j.appender.R.layout.ConversionPattern=%p %t %c - %m%n

　　2 建立初始化Action Servlet

　　import com.nova.colimas.web.constants.*;import org.apache.log4j.*;public class StartupServlet extends Action { public ActionForward execute(ActionMapping mapping,

　　ActionForm form,

　　HttpServletRequest request,

　　HttpServletResponse response) throws Exception{

　　try{//初始化log

　　initLog();

　　}catch(Exception e){

　　e.printStackTrace();

　　return mapping.findForward("failure");

　　}

　　Logger logger = Logger.getLogger(this.getClass());

　　logger.info("init log...");

　　}

　　private void initLog() throws Exception{//获得log.properties绝对地址

　　java.net.URL myfile=this.getClass().getResource("/resources/log/properties");//加载log配置文件log.properties

　　if(myfile.getPath()!=null)

　　PropertyConfigurator.configure(myfile.getPath());

　　else

　　throw new Exception("no log configure"); }}

　　3 写log

　　ublic class LoginAction extends Action {

　　LoginContext loginContext=null;

　　LoginForm loginForm=null;

　　public ActionForward execute(ActionMapping mapping,

　　ActionForm form,

　　HttpServletRequest request,

　　HttpServletResponse response)

　　throws Exception{

　　Logger logger = Logger.getLogger(this.getClass());

　　logger.info("login success");

　　return mapping.findForward("success");

　　}}

　　log文件内容如下：

　　INFO http-8080-Processor24 com.nova.colimas.web.action.StartupServlet - init colimas...INFO http-8080-Processor24 com.nova.colimas.web.action.StartupServlet - init security successfullyINFO http-8080-Processor24 com.nova.colimas.web.action.StartupServlet - init DAO successfullyINFO http-8080-Processor24 com.nova.colimas.web.action.LoginAction - login success