SpringMVC4整合Log4j
本节，将分享如何在一个SpringMVC web应用中整合log4j记录系统日志。
更多精彩请阅读 东陆之滇的csdn博客：http://blog.csdn.net/zixiao217
准备工作（根据自己的要求调整）
- Log4j 1.2.17
- Spring 4.2.5.RELEASE
- Maven 3
- Tomcat 9
- Eclipse neon版本
注意
默认情况下，Spring(Spring-core)使用JCL（commons-logging）记录日志，JCL在运行时可以发现其他classpath下的日志框架
集成log4j，你需要：
- 将log4j.jar添加到classpath中
- 在classpath下创建一个
log4j.properties或log4j.xml文件，如果使用maven风格的结构，放置在src/main/resources目录下
1. 工程目录
2. 项目依赖
完整的pom.xml
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>org.byron4j</groupId>
<artifactId>spring-mvc-log4j</artifactId>
<version>1.0.0-SNAPSHOT</version>
<packaging>war</packaging>
<name>spring-mvc-log4j</name>
<url>http://blog.csdn.net/zixiao217</url>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<spring.version>4.2.5.RELEASE</spring.version>
<log4j.version>1.2.17</log4j.version>
</properties>
<dependencies>
<!-- Spring -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>${spring.version}</version>
</dependency>
<!-- Log4j -->
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>${log4j.version}</version>
</dependency>
<!-- https://mvnrepository.com/artifact/javax.servlet/servlet-api -->
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>servlet-api</artifactId>
<version>2.5</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>3.8.1</version>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.5.1</version>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
</plugins>
</build>
</project>3. log4j.properties
log4j.rootLogger=info, stdout, file
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target=System.out
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss} %-5p %c{1}:%L - %m%n
log4j.appender.file=org.apache.log4j.RollingFileAppender
log4j.appender.file.File=E:\eclipse-logspring-mvc-log4j.log
log4j.appender.file.MaxFileSize=5MB
log4j.appender.file.MaxBackupIndex=10
log4j.appender.file.layout=org.apache.log4j.PatternLayout
log4j.appender.file.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss.S} %-5p %c{1}:%L - %m%n4. web.xml
<web-app xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
version="2.5">
<display-name>Gradle + Spring MVC Hello World + XML</display-name>
<description>Spring MVC web application</description>
<welcome-file-list>
<welcome-file>
/index.jsp
</welcome-file>
</welcome-file-list>
<!-- For web context -->
<servlet>
<servlet-name>hello-dispatcher</servlet-name>
<servlet-class>
org.springframework.web.servlet.DispatcherServlet
</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/spring-mvc-config.xml</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>hello-dispatcher</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
<!-- For root context -->
<listener>
<listener-class>
org.springframework.web.context.ContextLoaderListener
</listener-class>
</listener>
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/spring-mvc-config.xml</param-value>
</context-param>
</web-app>5. SpringMVC配置文件
spring-mvc-config.xml:
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xsi:schemaLocation="
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/mvc
http://www.springframework.org/schema/mvc/spring-mvc.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context.xsd ">
<context:component-scan base-package="org.byron4j" />
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="viewClass" value="org.springframework.web.servlet.view.JstlView"/>
<property name="prefix" value="/WEB-INF/views/jsp/" />
<property name="suffix" value=".jsp" />
</bean>
<mvc:resources mapping="/resources/**" location="/resources/" />
<mvc:annotation-driven />
</beans>6. 编写SpringMVC Controller + logging
WelcomeController.java类:
package org.byron4j.spring_mvc_log4j;
import org.apache.log4j.Logger;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.RestController;
/**
* Hello world!
*
*/
@RestController
public class WelcomeController
{
private static Logger logger = Logger.getLogger(WelcomeController.class);
@RequestMapping("/welcome")
@ResponseBody
public String getAppName(){
logger.info("访问首页");
return "<h1>SpringMVC integrate log4j - a demo</h1>";
}
}
7. 运行SpringMVC web应用
在浏览器访问http://localhost:8080/spring-mvc-log4j/welcome，界面： 
控制台输出:2016-10-27 00:33:07 INFO WelcomeController:20 - 访问首页
在指定的目录E:eclipse-log下生成了日志文件spring-mvc-log4j.log，打开看到内容：
2016-10-27 00:44:50.489 INFO ContextLoader:305 - Root WebApplicationContext: initialization started
2016-10-27 00:44:50.676 INFO XmlWebApplicationContext:578 - Refreshing Root WebApplicationContext: startup date [Thu Oct 27 00:44:50 CST 2016]; root of context hierarchy
2016-10-27 00:44:50.771 INFO XmlBeanDefinitionReader:317 - Loading XML bean definitions from ServletContext resource [/WEB-INF/spring-mvc-config.xml]
2016-10-27 00:44:51.660 INFO SimpleUrlHandlerMapping:341 - Mapped URL path [/resources/**] onto handler 'org.springframework.web.servlet.resource.ResourceHttpRequestHandler#0'
2016-10-27 00:44:51.758 INFO RequestMappingHandlerMapping:534 - Mapped "{[/welcome]}" onto public java.lang.String org.byron4j.spring_mvc_log4j.WelcomeController.getAppName()
2016-10-27 00:44:51.856 INFO RequestMappingHandlerAdapter:532 - Looking for @ControllerAdvice: Root WebApplicationContext: startup date [Thu Oct 27 00:44:50 CST 2016]; root of context hierarchy
2016-10-27 00:44:51.932 INFO RequestMappingHandlerAdapter:532 - Looking for @ControllerAdvice: Root WebApplicationContext: startup date [Thu Oct 27 00:44:50 CST 2016]; root of context hierarchy
2016-10-27 00:44:52.29 INFO ContextLoader:345 - Root WebApplicationContext: initialization completed in 1536 ms
2016-10-27 00:44:52.53 INFO DispatcherServlet:488 - FrameworkServlet 'hello-dispatcher': initialization started
2016-10-27 00:44:52.57 INFO XmlWebApplicationContext:578 - Refreshing WebApplicationContext for namespace 'hello-dispatcher-servlet': startup date [Thu Oct 27 00:44:52 CST 2016]; parent: Root WebApplicationContext
2016-10-27 00:44:52.58 INFO XmlBeanDefinitionReader:317 - Loading XML bean definitions from ServletContext resource [/WEB-INF/spring-mvc-config.xml]
2016-10-27 00:44:52.128 INFO SimpleUrlHandlerMapping:341 - Mapped URL path [/resources/**] onto handler 'org.springframework.web.servlet.resource.ResourceHttpRequestHandler#0'
2016-10-27 00:44:52.139 INFO RequestMappingHandlerMapping:534 - Mapped "{[/welcome]}" onto public java.lang.String org.byron4j.spring_mvc_log4j.WelcomeController.getAppName()
2016-10-27 00:44:52.156 INFO RequestMappingHandlerAdapter:532 - Looking for @ControllerAdvice: WebApplicationContext for namespace 'hello-dispatcher-servlet': startup date [Thu Oct 27 00:44:52 CST 2016]; parent: Root WebApplicationContext
2016-10-27 00:44:52.166 INFO RequestMappingHandlerAdapter:532 - Looking for @ControllerAdvice: WebApplicationContext for namespace 'hello-dispatcher-servlet': startup date [Thu Oct 27 00:44:52 CST 2016]; parent: Root WebApplicationContext
2016-10-27 00:44:52.239 INFO DispatcherServlet:507 - FrameworkServlet 'hello-dispatcher': initialization completed in 185 ms
2016-10-27 00:44:58.298 INFO WelcomeController:20 - 访问首页结束了。这里又搭了一遍SpringMVC配置哦。。。