4.Spring中使用Log4j

转自：https://blog.csdn.net/luohai859/article/details/52250807

这里要实现web项目中利用Spring来使用Log4j

（1）接上面的工程，然后再导入Spring的包

（2）web.xml增加

 1 <!-- 设置根目录 -->  
 2    <context-param>    
 3        <param-name>webAppRootKey</param-name>    
 4        <param-value>webapp.root</param-value>    
 5    </context-param>    
 6 
 7    <context-param>  
 8     <param-name>log4jConfigLocation</param-name>  
 9     <param-value>/WEB-INF/classes/log4j.properties</param-value>  
10 </context-param>  
11 <!-- 3000表示 开一条watchdog线程每60秒扫描一下配置文件的变化;这样便于日志存放位置的改变 -->  
12 <context-param>    
13         <param-name>log4jRefreshInterval</param-name>    
14         <param-value>3000</param-value>    
15    </context-param>   
16 <listener>  
17     <listener-class>org.springframework.web.util.Log4jConfigListener</listener-class>  
18 </listener>

整个内容如下：

 1 <?xml version="1.0" encoding="UTF-8"?>  
 2 <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"  
 3     xmlns="http://java.sun.com/xml/ns/javaee"  
 4     xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"  
 5     id="WebApp_ID" version="3.0">  
 6     <display-name>LogLearning</display-name>  
 7 
 8     <servlet>  
 9         <servlet-name>Log4JTestServlet</servlet-name>  
10         <servlet-class>com.mucfc.Log4JTestServlet</servlet-class>  
11     </servlet>  
12 
13     <!--用来启动 log4jConfigLocation的servlet -->  
14 <!--     <servlet>  
15         <servlet-name>Log4JInitServlet</servlet-name>  
16         <servlet-class>com.mucfc.Log4JInitServlet</servlet-class>  
17         <init-param>  
18             <param-name>log4j-properties-location</param-name>  
19             <param-value>/WEB-INF/classes/log4j.properties</param-value>  
20         </init-param>  
21         <load-on-startup>1</load-on-startup>  
22     </servlet>-->  
23 
24     <servlet-mapping>  
25         <servlet-name>Log4JTestServlet</servlet-name>  
26         <url-pattern>/test</url-pattern>  
27     </servlet-mapping>   
28 
29         <!-- Spring 容器加载 -->  
30     <listener>  
31         <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>  
32     </listener>  
33     <context-param>  
34         <param-name>contextConfigLocation</param-name>  
35         <param-value>classpath:applicationContext.xml</param-value>  
36     </context-param>   
37 
38     <!-- 设置根目录 -->  
39     <context-param>    
40         <param-name>webAppRootKey</param-name>    
41         <param-value>webapp.root</param-value>    
42     </context-param>    
43 
44     <context-param>  
45         <param-name>log4jConfigLocation</param-name>  
46         <param-value>/WEB-INF/classes/log4j.properties</param-value>  
47     </context-param>  
48     <!-- 3000表示 开一条watchdog线程每60秒扫描一下配置文件的变化;这样便于日志存放位置的改变 -->  
49     <context-param>    
50          <param-name>log4jRefreshInterval</param-name>    
51          <param-value>3000</param-value>    
52     </context-param>   
53     <listener>  
54         <listener-class>org.springframework.web.util.Log4jConfigListener</listener-class>  
55     </listener>   
56 
57 </web-app>

这里Log4JInitServlet.java就相当于没用到了。

（2）applicationContext.xml

没有内容：

<?xml version="1.0" encoding="UTF-8"?>  
<beans xmlns="http://www.springframework.org/schema/beans"  
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context"  
    xmlns:aop="http://www.springframework.org/schema/aop"  
    xsi:schemaLocation="    

http://www.springframework.org/schema/beans


http://www.springframework.org/schema/beans/spring-beans-3.2.xsd


http://www.springframework.org/schema/aop


http://www.springframework.org/schema/aop/spring-aop-3.2.xsd


http://www.springframework.org/schema/context

           http://www.springframework.org/schema/context/spring-context-3.2.xsd">  
</beans>

（3）这样日志就跟随Spring窗口启动而启动了

程序一运行，就会自动把日志打印

log.log

error.log为空，因为它只打印error级别以上的信息

浏览器输入http://localhost:8080/LogLearning2/test

然后打开文件