学步园

1、下載Log4j.jar

http://www.apache.org

2、寫一個servlet(網上有)

package Log4j;

import org.apache.log4j.PropertyConfigurator;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 *
 * @author tao
 */
public class Log4jInit extends HttpServlet{
    public void init(){
        String prefix = getServletContext().getRealPath("/");
 String file = getInitParameter("log4j");
        //if the log4j-init-file is not set, then no point in trying
 System.out.println("................log4j start");
 if(file != null){
            PropertyConfigurator.configure(prefix+file);
 }
    }
    public void doGet(HttpServletRequest req, HttpServletResponse res) {
       
    }
}

3、配置web.xml

<servlet>
        <servlet-name>log4-init</servlet-name>
        <servlet-class>Log4j.Log4jInit</servlet-class>
        <init-param>
            <param-name>log4j</param-name>
            <param-value>/WEB-INF/log4j.properties</param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
  </servlet>

4、加一個log4j.properties，放在WEB-INF中

log4j.rootLogger=DEBUG, A1,A2
log4j.appender.A1=org.apache.log4j.ConsoleAppender
log4j.appender.A1.layout=org.apache.log4j.PatternLayout
log4j.appender.A2=org.apache.log4j.DailyRollingFileAppender
log4j.appender.A2.file=C://Test
log4j.appender.A2.DatePattern='.'yyyy-MM-dd'.log'
log4j.appender.A2.layout=org.apache.log4j.PatternLayout
log4j.appender.A2.layout.ConversionPattern=%d [%t][%-5p] %c{2} - %m%n

5、寫一個jsp文件

<%@page contentType="text/html"%>
<%@page pageEncoding="UTF-8"%>
<%@ page import="org.apache.log4j.*" %>
<%
       Logger logger = Logger.getLogger("test.jsp");
       logger.info("Info1");
       logger.error("Error2~!");
       logger.warn("Warn3~!");
       logger.debug("Debug4");
%>
<h1> Hi</h1>

就這樣，我測試通過了。