Log4J配置与初始化-优快云博客

本文介绍如何通过创建Log4Init类并在web.xml中配置来初始化Log4J，包括使用ConsoleAppender和DailyRollingFileAppender进行日志输出。

1. 首先建一个初始Log4Init类

其中需入导入包: log4j-1.2.8.jar, tomcat/bin目录下的servlet-api.jar

Log4Init.java

import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;

import org.apache.log4j.Logger;
import org.apache.log4j.PropertyConfigurator;

public class Log4Init extends HttpServlet {
	
	private static final long serialVersionUID = 7788159703223986067L;
	static Logger log = Logger.getLogger(Log4Init.class);
	
	public void init() throws ServletException{
		ServletConfig config = getServletConfig();
		String path = config.getServletContext().getRealPath("/");
		PropertyConfigurator.configure(path + "WEB-INF/classes/log4j.properties");
		log.info(" 初始化---------Log4J------");
	}

}

2. 然后在web.xml 配置初始化

web.xml

<!-- Log4Init -->
    <servlet>
    	<servlet-name>log</servlet-name>
         <servlet-class>cn.ssh.struts.select.Log4Init</servlet-class>
         <load-on-startup>1</load-on-startup>
    </servlet>

3. 增加配置文件.

log4j.properties

# This is the configuring for logging displayed in the Application Server
log4j.rootCategory=INFO,stdout,logfile

#stdout configure
log4j.appender.stdout = org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern= %d %p [%c] %L - <%m>%n 

#logfile configure
log4j.appender.logfile=org.apache.log4j.DailyRollingFileAppender
#log4j.appender.logfile.DatePattern=.yyyy-MM-dd-HH-mm'.log'
#log4j.appender.logfile.File=${catalina.base}/logs/smartcom.log
log4j.appender.logfile.File=${catalina.base}/logs/ssh_xml.log
log4j.appender.logfile.DatePattern='_'yyyy-MM-dd-HH-mm'.log'  
log4j.appender.logfile.layout=org.apache.log4j.PatternLayout
#log4j.appender.logfile.layout.ConversionPattern=%d %p [%c] - <%m>%n
log4j.appender.logfile.layout.ConversionPattern=%-d{yyyy-MM-dd   HH\:mm\:ss}   [%c]-[%p]   %m%n

Log4J 配置