SpringBoot 引入log4j2日志框架

1. 排除SpringBoot自带的日志框架
   pom.xml

     <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
            <exclusions>
                <exclusion>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-starter-logging</artifactId>
                </exclusion>
            </exclusions>
        </dependency>

2. 添加 log4j2依赖

 <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-log4j2</artifactId>
        </dependency>

3. 使用lombok的@SIf4j 注解，省去配置生命log

        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>

4. 在resource文件夹下添加log42.xml文件

<?xml version="1.0" encoding="UTF-8"?>
<configuration status="OFF">
    <appenders>
        <Console name="Console" target="SYSTEM_OUT">
            <ThresholdFilter level="DEBUG" onMatch="ACCEPT" onMismatch="DENY"/>
            <PatternLayout pattern="[%d{yyyy-MM-dd HH:mm:ss.SSS}] %-5level - %msg%xEx%n"/>
        </Console>

        <RollingFile name="RollingFileDebug" fileName="./logs/debug.log"
                     filePattern="logs/$${date:yyyy-MM}/debug-%d{yyyy-MM-dd}-%i.log.gz">
            <Filters>
                <ThresholdFilter level="DEBUG"/>
                <ThresholdFilter level="INFO" onMatch="DENY" onMismatch="NEUTRAL"/>
            </Filters>
            <PatternLayout pattern="[%d{yyyy-MM-dd HH:mm:ss.SSS}] %class{36} %L %M - %msg%xEx%n"/>
            <Policies>
                <SizeBasedTriggeringPolicy size="100 MB"/>
                <TimeBasedTriggeringPolicy/>
            </Policies>
            <DefaultRolloverStrategy>
                <Delete basePath="logs" maxDepth="2">
                    <IfFileName glob="*/debug-*.log.gz" />
                    <IfLastModified age="30d" />
                </Delete>
            </DefaultRolloverStrategy>
        </RollingFile>

        <RollingFile name="RollingFileInfo" fileName="./logs/info.log"
                     filePattern="logs/$${date:yyyy-MM}/info-%d{yyyy-MM-dd}-%i.log.gz">
            <Filters>
                <ThresholdFilter level="INFO"/>
                <ThresholdFilter level="WARN" onMatch="DENY" onMismatch="NEUTRAL"/>
            </Filters>
            <PatternLayout pattern="[%d{yyyy-MM-dd HH:mm:ss.SSS}] %class{36} %L %M - %msg%xEx%n"/>
            <Policies>
                <SizeBasedTriggeringPolicy size="50 MB"/>
                <TimeBasedTriggeringPolicy/>
            </Policies>
            <DefaultRolloverStrategy>
                <Delete basePath="logs" maxDepth="2">
                    <IfFileName glob="*/info-*.log.gz" />
                    <IfLastModified age="30d" />
                </Delete>
            </DefaultRolloverStrategy>
        </RollingFile>

        <RollingFile name="RollingFileWarn" fileName="./logs/warn.log"
                     filePattern="logs/$${date:yyyy-MM}/warn-%d{yyyy-MM-dd}-%i.log.gz">
            <Filters>
                <ThresholdFilter level="WARN"/>
                <ThresholdFilter level="ERROR" onMatch="DENY" onMismatch="NEUTRAL"/>
            </Filters>
            <PatternLayout
                    pattern="[%d{yyyy-MM-dd HH:mm:ss.SSS}] %class{36} %L %M - %msg%xEx%n"/>
            <Policies>
                <SizeBasedTriggeringPolicy size="50 MB"/>
                <TimeBasedTriggeringPolicy/>
            </Policies>
            <DefaultRolloverStrategy>
                <Delete basePath="logs" maxDepth="2">
                    <IfFileName glob="*/warn-*.log.gz" />
                    <IfLastModified age="30d" />
                </Delete>
            </DefaultRolloverStrategy>
        </RollingFile>

        <RollingFile name="RollingFileError" fileName="./logs/error.log"
                     filePattern="logs/$${date:yyyy-MM}/error-%d{yyyy-MM-dd}-%i.log.gz">
            <ThresholdFilter level="ERROR"/>
            <PatternLayout pattern="[%d{yyyy-MM-dd HH:mm:ss.SSS}] %class{36} %L %M - %msg%xEx%n"/>
            <Policies>
                <SizeBasedTriggeringPolicy size="50 MB"/>
                <TimeBasedTriggeringPolicy/>
            </Policies>
            <DefaultRolloverStrategy>
                <Delete basePath="logs" maxDepth="2">
                    <IfFileName glob="*/error-*.log.gz" />
                    <IfLastModified age="30d" />
                </Delete>
            </DefaultRolloverStrategy>
        </RollingFile>
    </appenders>

    <loggers>
        <root level="INFO">
            <appender-ref ref="Console"/>
            <appender-ref ref="RollingFileInfo"/>
            <appender-ref ref="RollingFileWarn"/>
            <appender-ref ref="RollingFileError"/>
            <appender-ref ref="RollingFileDebug"/>
        </root>

        <logger name="com.demo" level="DEBUG" />

    </loggers>
</configuration>

5. 在application.yml文件中设置log4j2.xml文件的路径

logging:
  config: classpath:log4j2.xml

6. 测试

@Slf4j
class DemoApplicationTests {

    @Test
    public void log4j2Test() {

        System.out.println("log4j2测试");
        log.info("info日志");
        log.warn("warn日志");
        log.debug("debug日志");
        log.error("error日志");

    }

}