<!-- Exclude Spring Boot's Default Logging -->
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter</artifactId>
    <exclusions>
        <exclusion>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-logging</artifactId>
        </exclusion>
    </exclusions>
</dependency>

<!-- Add Log4j2 Dependency -->
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-log4j2</artifactId>
</dependency>

<!-- Needed for Async Logging with Log4j 2 -->
<dependency>
  <groupId>com.lmax</groupId>
  <artifactId>disruptor</artifactId>
  <version>3.3.6</version>
</dependency>

<!-- 使用jsonLayout必须依赖jackson -->
<dependency>
  <groupId>com.fasterxml.jackson.core</groupId>
  <artifactId>jackson-core</artifactId>
  <version>2.7.4</version>
</dependency>
<dependency>
  <groupId>com.fasterxml.jackson.core</groupId>
  <artifactId>jackson-databind</artifactId>
  <version>2.7.4</version>
</dependency>

<?xml version="1.0" encoding="UTF-8"?>
<!-- status表示log4j2本身的日志信息打印级别，和下面的level，不是一个概念 -->
<!--TRACE < DEBUG < INFO < WARN < ERROR < FATAL < OFF-->
<Configuration status="OFF" monitorInterval="30">
    <Properties>
        <Property name="LOG_PATTERN">
            %d{yyyy-MM-dd HH:mm:ss.SSS} %5p ${hostName} -&#45;&#45; [%15.15t] %-40.40c{1.} : %m%n%ex
        </Property>
        <Property name="LOG_FILE_PATH">/var/log/spring-boot-log4j2</Property>
    </Properties>
    <Appenders>
        <Console name="ConsoleAppender" target="SYSTEM_OUT" follow="true">
            <PatternLayout pattern="${LOG_PATTERN}"/>
        </Console>
        <!-- Rolling File Appender -->
        <RollingFile name="FileAppender" fileName="${LOG_FILE_PATH}/spring-boot-log4j2-demo.log"
                     filePattern="${LOG_FILE_PATH}/spring-boot-log4j2-demo-%d{yyyy-MM-dd}-%i.log">
            <PatternLayout>
                <Pattern>${LOG_PATTERN}</Pattern>
            </PatternLayout>
            <!--<JsonLayout complete="false" compact="true">
                <KeyValuePair key="timestamp" value="$${date:yyyy-MM-dd'T'HH:mm:ss.SSSZ}" />
            </JsonLayout>-->
            <Filters>
                <!-- 只记录ERROR级别日志信息，程序打印的其他信息不会被记录 -->
                <!-- 此level设置的日志级别，是过滤日志文件中打印出的日志信息，和Root的level有所区别 -->
                <ThresholdFilter level="ERROR" onMatch="ACCEPT" onMismatch="DENY" />
            </Filters>
            <Policies>
                <SizeBasedTriggeringPolicy size="10MB" />
                <!-- 每天创建一个日志文件 -->
                <TimeBasedTriggeringPolicy interval="1" />
            </Policies>
            <DefaultRolloverStrategy max="10"/>
        </RollingFile>
    </Appenders>
    <Loggers>
        <!-- 用来单独指定日志的形式，比如要为指定包下的class指定不同的日志级别等。 -->
        <!--<Logger name="com.easyjijin.demo.springbootlog4j2" level="debug" additivity="false">
            <AppenderRef ref="ConsoleAppender" />
            <AppenderRef ref="FileAppender"/>
        </Logger>-->

        <!-- AsyncRoot - 异步记录日志 - 需要LMAXDisruptor的支持 -->
        <!-- <AsyncRootlevel="info" additivity="false">
          <AppenderRef ref="Console"/>
          <AppenderRef ref="FileAppender"/>
        </AsyncRoot> -->

        <!-- All < Trace < Debug < Info < Warn < Error < Fatal < OFF. -->
　　　　 <!-- 程序会打印高于或等于所设置级别的日志，设置的日志等级越高，打印出来的日志就越少。-->
        <!-- 此level设置的日志级别，是过滤项目中输出的日志信息，和ThresholdFilter的level有所区别 -->
        <Root level="ERROR">
            <AppenderRef ref="ConsoleAppender" />
            <AppenderRef ref="FileAppender"/>
        </Root>
    </Loggers>
</Configuration>

@SpringBootApplication
public class Log4j2DemoApplication implements ApplicationRunner {
    private static final Logger logger = LogManager.getLogger(Log4j2DemoApplication.class);

    public static void main(String[] args) {
        SpringApplication.run(Log4j2DemoApplication.class, args);
    }

    @Override
    public void run(ApplicationArguments applicationArguments) throws Exception {
        logger.debug("Debugging log");
        logger.info("Info log");
        logger.warn("Hey, This is a warning!");
        logger.error("Oops! We have an Error. OK");
        logger.fatal("Damn! Fatal error. Please fix me.");
    }
}

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

import lombok.extern.log4j.Log4j2;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@Log4j2
@RestController
public class HelloController {

    @RequestMapping("/home")
    public String home() {

        log.error("Hi ! We have an Error. Hello World");

        return "Hello World ----spring-boot-log4j2";
    }
}