一、依赖的包
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
private static final Logger LOGGER = LoggerFactory.getLogger(UserController.class);
<apache.log4j2.version>2.7</apache.log4j2.version> ???<slf4j.version>1.7.22</slf4j.version> <dependency> ?????<groupId>org.slf4j</groupId> ?????<artifactId>slf4j-api</artifactId> ?????<version>${slf4j.version}</version> ???</dependency> ???<dependency> ?????<groupId>org.slf4j</groupId> ?????<artifactId>jcl-over-slf4j</artifactId> ?????<version>${slf4j.version}</version> ???</dependency> ???<dependency> ?????<groupId>org.apache.logging.log4j</groupId> ?????<artifactId>log4j-slf4j-impl</artifactId> ?????<version>${apache.log4j2.version}</version> ???</dependency> ???<dependency> ?????<groupId>org.apache.logging.log4j</groupId> ?????<artifactId>log4j-core</artifactId> ?????<version>${apache.log4j2.version}</version> ???</dependency> ???<dependency> ?????<groupId>org.apache.logging.log4j</groupId> ?????<artifactId>log4j-api</artifactId> ?????<version>${apache.log4j2.version}</version> ???</dependency> ???<dependency> ?????<groupId>org.apache.logging.log4j</groupId> ?????<artifactId>log4j-web</artifactId> ?????<version>${apache.log4j2.version}</version> ???</dependency>二、web.xml配置log4j2的监听器
<!--设置log4j的配置文件位置--> ?<context-param> ???<param-name>log4jConfigLocation</param-name> ???<param-value>classpath:log4j2.xml</param-value> ?</context-param> <listener> ???<listener-class>org.apache.logging.log4j.web.Log4jServletContextListener</listener-class> ?</listener> ?<filter> ???<filter-name>log4jServletFilter</filter-name> ???<filter-class>org.apache.logging.log4j.web.Log4jServletFilter</filter-class> ?</filter> ?<filter-mapping> ???<filter-name>log4jServletFilter</filter-name> ???<url-pattern>/*</url-pattern> ???<dispatcher>REQUEST</dispatcher> ???<dispatcher>FORWARD</dispatcher> ???<dispatcher>INCLUDE</dispatcher> ???<dispatcher>ERROR</dispatcher> ?</filter-mapping>
三、如果项目是maven所建，把log4j2.xml放在根目录下
<?xml version="1.0" encoding="UTF-8"?><configuration monitorInterval="30" status="DEBUG"> ?<Properties> ???<Property name="fileName">myLog.log</Property> ???<Property name="backupFilePatch">/Users/study-hello/spring-web/logs</Property> ?</Properties> ?<!--先定义所有的appender--> ?<appenders> ???<!--这个输出控制台的配置--> ???<Console name="Console" target="SYSTEM_OUT"> ?????<!--控制台只输出level及以上级别的信息（onMatch），其他的直接拒绝（onMismatch）--> ?????<ThresholdFilter level="DEBUG" onMatch="ACCEPT" onMismatch="DENY"/> ?????<!--这个都知道是输出日志的格式--> ?????<PatternLayout charset="UTF-8" ???????pattern="%d{yyyy-MM-dd HH:mm:ss.SSS} [%-5level] %-10C %M %L: %m%n"/> ???</Console> ???<RollingFile fileName="${backupFilePatch}/debug.log" ?????filePattern="${backupFilePatch}/$${date:yyyy-MM}/%d{yyyy-MM-dd}.debug.log" ?????name="RollingFileDebug"> ?????<Filters> ???????<ThresholdFilter level="INFO" onMatch="DENY" onMismatch="NEUTRAL"/> ???????<ThresholdFilter level="DEBUG" onMatch="ACCEPT" onMismatch="DENY"/> ?????</Filters> ?????<PatternLayout charset="UTF-8" ???????pattern="%d{yyyy-MM-dd HH:mm:ss.SSS z} [%-5level] %C %M %L: %m%n"/> ?????<Policies> ???????<TimeBasedTriggeringPolicy interval="1" modulate="true"/> ?????????</Policies> ???</RollingFile> ???<RollingFile fileName="${backupFilePatch}/info.log" ?????filePattern="${backupFilePatch}/$${date:yyyy-MM}/%d{yyyy-MM-dd}.info.log" ?????name="RollingFileInfo"> ?????<Filters> ???????<ThresholdFilter level="WARN" onMatch="DENY" onMismatch="NEUTRAL"/> ???????<ThresholdFilter level="INFO" onMatch="ACCEPT" onMismatch="DENY"/> ?????</Filters> ?????<PatternLayout charset="UTF-8" ???????pattern="%d{yyyy-MM-dd HH:mm:ss.SSS z} [%-5level] %C %M %L: %m%n"/> ?????<Policies> ???????<TimeBasedTriggeringPolicy interval="1" modulate="true"/> ?????</Policies> ???</RollingFile> ???<RollingFile fileName="${backupFilePatch}/warn.log" ?????filePattern="${backupFilePatch}/$${date:yyyy-MM}/%d{yyyy-MM-dd}.warn.log" ?????name="RollingFileWarn"> ?????<Filters> ???????<ThresholdFilter level="ERROR" onMatch="DENY" onMismatch="NEUTRAL"/> ???????<ThresholdFilter level="WARN" onMatch="ACCEPT" onMismatch="DENY"/> ?????</Filters> ?????<!-- ?z 表示时区 --> ?????<PatternLayout charset="UTF-8" ???????pattern="%d{yyyy-MM-dd HH:mm:ss.SSS z} [%-5level] %C %M %L: %m%n"/> ?????<Policies> ???????<TimeBasedTriggeringPolicy interval="1" modulate="true"/> ???????</Policies> ???</RollingFile> ???<RollingFile fileName="${backupFilePatch}/error.log" ?????filePattern="${backupFilePatch}/$${date:yyyy-MM}/%d{yyyy-MM-dd}.error.log" ?????name="RollingFileError"> ?????<ThresholdFilter level="ERROR" onMatch="ACCEPT" onMismatch="DENY"/> ?????<!-- ?z 表示时区 --> ?????<PatternLayout charset="UTF-8" ???????pattern="%d{yyyy-MM-dd HH:mm:ss.SSS z} [%-5level] %C %M %L: %m%n"/> ?????<Policies> ???????<TimeBasedTriggeringPolicy interval="1" modulate="true"/> ?????</Policies> ???</RollingFile> ?</appenders> ?<!--然后定义logger，只有定义了logger并引入的appender，appender才会生效--> ?<loggers> ?????<Logger level="DEBUG" name="com.ibatis"> ?????<AppenderRef ref="RollingFileDebug"/> ?????<AppenderRef ref="RollingFileInfo"/> ?????<AppenderRef ref="RollingFileWarn"/> ?????<AppenderRef ref="RollingFileError"/> ???</Logger> ???????<Root level="DEBUG"> ?????<!--AppenderRef：Root的子节点，用来指定该日志输出到哪个Appender. --> ?????<AppenderRef ref="Console"/> ?????<AppenderRef ref="RollingFileDebug"/> ?????<AppenderRef ref="RollingFileInfo"/> ?????<AppenderRef ref="RollingFileWarn"/> ?????<AppenderRef ref="RollingFileError"/> ???</Root> ?</loggers></configuration>log4j2在web中的使用
原文地址：http://www.cnblogs.com/liuzyw/p/7622227.html