log4j2分层输出日志

在java mvc框架开发过程中，我们经常的将代码分为类似controller（控制层）、service（业务层）、rpc（远程接口调用层）、dao（数据层）等层级，如果将所有层级的日志全部都打到一个文件，一个是导致单个日志文件过大，另外不方便查看，所以下面考虑用log4j2根据不同层级生成对应的log文件：

1. maven配置

<dependency>
            <groupid>org.slf4j</groupid>
            <artifactid>slf4j-api</artifactid>
        </dependency>
        <dependency>
            <groupid>org.slf4j</groupid>
            <artifactid>slf4j-log4j12</artifactid>
        </dependency>
        <dependency>
            <groupid>org.apache.logging.log4j</groupid>
            <artifactid>log4j-1.2-api</artifactid>
            <version>2.10.0</version>
        </dependency>           

2. log4j2配置文件

<?xml version="1.0" encoding="utf-8"?>
<configuration status="warn" monitorinterval="30">
    <properties>
        <!-- 文件输出格式 -->
        <property name="pattern">%d{yyyy-mm-dd hh:mm:ss.sss} |-%-5level [logid:%x{logid}] [%thread] %c#%m [%l] -| %msg%n</property>
        <property name="filepath">/export/logs/domains/myapp</property>
    </properties>

    <appenders>
        <console name="console" target="system_out">
            <patternlayout pattern="${pattern}" />
        </console>
        <rollingrandomaccessfile name="rpcfile" filename="${filepath}/rpc.log" filepattern="${filepath}/rpc-%d{yyyy-mm-dd}.log">
            <patternlayout pattern="${pattern}"/>
            <policies>
                <timebasedtriggeringpolicy modulate="true" interval="1"/>
            </policies>
        </rollingrandomaccessfile>

        <rollingrandomaccessfile name="servicefile" filename="${filepath}/service.log" filepattern="${filepath}/service-%d{yyyy-mm-dd}.log">
            <patternlayout pattern="${pattern}"/>
            <policies>
                <timebasedtriggeringpolicy modulate="true" interval="1"/>
            </policies>
        </rollingrandomaccessfile>
        <rollingrandomaccessfile name="controllerfile" filename="${filepath}/controller.log" filepattern="${filepath}/controller-%d{yyyy-mm-dd}.log">
            <patternlayout pattern="${pattern}"/>
            <policies>
                <timebasedtriggeringpolicy modulate="true" interval="1"/>
            </policies>
        </rollingrandomaccessfile>

    </appenders>

    <loggers>
        <!--过滤信息-->
        <logger name="org.springframework" level="warn"></logger>
        <logger name="rpc" level="info" >
            <appenderref ref="rpcfile" />
        </logger>
        <logger name="service" level="info" >
            <appenderref ref="servicefile" />
        </logger>
        <logger name="controller" level="info" >
            <appenderref ref="controllerfile" />
        </logger>
        <root level="info">
            <appenderref ref="console" />
            <appenderref ref="exceptionfile" />
        </root>
    </loggers>

</configuration>

3. 输出日志工具类

import org.slf4j.logger;
import org.slf4j.loggerfactory;

public class logutil {

    /**
     * rpc层日志记录
     */
    public static final logger rpc = loggerfactory.getlogger("rpc");

    /**
     * service业务层日志记录
     */
    public static final logger service = loggerfactory.getlogger("service");

    /**
     * controller业务层日志记录
     */
    public static final logger controller = loggerfactory.getlogger("controller");

}

4. 输出日志

logutil.controller.error("error message={}", e);
logutil.service.warn("warn message={}", msg);
....