Log4j2 实例

1.Maven 配置

<!-- 日志 -->
<dependency>  
    <groupId>org.slf4j</groupId>  
    <artifactId>slf4j-api</artifactId>  
    <version>1.7.13</version>  
</dependency>  
<dependency>  
    <groupId>org.slf4j</groupId>  
    <artifactId>jcl-over-slf4j</artifactId>  
    <version>1.7.13</version>  
    <scope>runtime</scope>  
</dependency>
<!-- 桥接：告诉Slf4j使用Log4j2 -->
<dependency> 
    <groupId>org.apache.logging.log4j</groupId>
    <artifactId>log4j-slf4j-impl</artifactId>
    <version>2.2</version>
</dependency>
<!-- 桥接：告诉commons logging使用Log4j2 -->
<dependency> 
    <groupId>org.apache.logging.log4j</groupId>
    <artifactId>log4j-jcl</artifactId>
    <version>2.2</version>
</dependency>
<!--须要使用log4j2的AsyncLogger须要包含disruptor-->  
<dependency>  
    <groupId>com.lmax</groupId>  
    <artifactId>disruptor</artifactId>  
    <version>3.2.0</version>  
</dependency>
<!-- log4j2 -->
<dependency>  
    <groupId>org.apache.logging.log4j</groupId>  
    <artifactId>log4j-api</artifactId>  
    <version>2.2</version>  
</dependency>  
<dependency>  
    <groupId>org.apache.logging.log4j</groupId>  
    <artifactId>log4j-core</artifactId>  
    <version>2.2</version>  
</dependency>  
<dependency>
    <groupId>org.apache.logging.log4j</groupId>
    <artifactId>log4j-web</artifactId>
    <version>2.2</version>
</dependency>

2.web.xml配置

<!--对于log4j2，Servlet2.5之前的版本须要-->  
<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>  

<!--log4j2再也不支持properties文件了，只支持xml，json或是yaml，默认在src/main/resources下查找。自定义位置，以下-->
<context-param>  
  <param-name>log4jConfiguration</param-name>  
  <param-value>/WEB-INF/classes/log4j2.xml</param-value>  
</context-param>

3.实例

<?xml version="1.0" encoding="UTF-8"?>
<!--日志级别以及优先级排序: OFF > FATAL > ERROR > WARN > INFO > DEBUG > TRACE > ALL -->
<!--Configuration后面的status，这个用于设置log4j2自身内部的信息输出，能够不设置，当设置成trace时，你会看到log4j2内部各类详细输出-->
<!--monitorInterval：Log4j可以自动检测修改配置 文件和从新配置自己，设置间隔秒数-->
<configuration status="WARN" monitorInterval="30">
    <properties><!-- 定义常量 -->  
        <property name="LOG_HOME">logs</property>  
        <property name="FILE_NAME">ams.bankage</property>
    </properties>    
    <!--先定义全部的appender-->
    <appenders>
    <!--这个输出控制台的配置-->
        <console name="Console" target="SYSTEM_OUT">
        <!--输出日志的格式-->
            <PatternLayout pattern="%-d{yyyy-MM-dd HH:mm:ss.SSS} [%t] - [%-5level] [%X{SEQ}] %logger{36} %L %M - %msg%xEx%n"/>
        </console>
        <!-- 这个会打印出全部的info及如下级别的信息，每次大小超过size，则这size大小的日志会自动存入按年份-月份创建的文件夹下面并进行压缩，做为存档-->
        <RollingFile name="RollingFileInfo" fileName="${LOG_HOME}/${FILE_NAME}-info.log"
                     filePattern="${LOG_HOME}/${FILE_NAME}-info-%d{yyyy-MM-dd}-%i.log">
            <!--控制台只输出level及以上级别的信息（onMatch），其余的直接拒绝（onMismatch）-->        
            <ThresholdFilter level="info" onMatch="ACCEPT" onMismatch="DENY"/>
            <PatternLayout pattern="%-d{yyyy-MM-dd HH:mm:ss.SSS} [%t] - [%-5level] [%X{SEQ}] %logger{36} %L %M - %msg%xEx%n"/>
            <Policies>
                <TimeBasedTriggeringPolicy/>
                <SizeBasedTriggeringPolicy size="100 MB"/>
            </Policies>
        </RollingFile>
        <RollingFile name="RollingFileError" fileName="${LOG_HOME}/${FILE_NAME}-error.log"
                     filePattern="${LOG_HOME}/${FILE_NAME}-error-%d{yyyy-MM-dd}-%i.log">
            <ThresholdFilter level="error" onMatch="ACCEPT" onMismatch="DENY"/>
            <PatternLayout pattern="%-d{yyyy-MM-dd HH:mm:ss.SSS} [%t] - [%-5level] [%X{SEQ}] %logger{36} %L %M - %msg%xEx%n"/>
            <Policies>
                <TimeBasedTriggeringPolicy/>
                <SizeBasedTriggeringPolicy size="100 MB"/>
            </Policies>
        </RollingFile>

    </appenders>
    <!--而后定义logger，只有定义了logger并引入的appender，appender才会生效-->
    <loggers>
        <Root level="INFO">
            <appender-ref ref="Console"/>
        </Root>

        <!-- 将业务dao接口填写进去,并用控制台输出便可 -->  
        <AsyncLogger  name="com.jf.ams" level="INFO" additivity="false" includeLocation="true">
            <appender-ref ref="Console"/>
            <AppenderRef ref="RollingFileInfo" />   
            <AppenderRef ref="RollingFileError"/>
        </AsyncLogger>

        <!-- 将业务dao接口填写进去,并用控制台输出便可 -->  
        <AsyncLogger name="com.jf.ams.bankpage.dao" level="DEBUG" additivity="false" includeLocation="true">  
            <appender-ref ref="Console"/>
        </AsyncLogger>

        <!--过滤掉spring和mybatis的一些无用的DEBUG信息-->
        <logger name="org.springframework.core" level="info"/>
        <logger name="org.springframework.beans" level="info"/>
        <logger name="org.springframework.context" level="info"/>
        <logger name="org.springframework.web" level="info"/>
    </loggers>
</configuration>