SpringBoot 官方文档示例：_java

一、配置pom.xml排除默认的logback并加入log4j2依赖，
完整Pom如下：

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>cn.edu.tju</groupId>
    <artifactId>springbootconfigtest3</artifactId>
    <version>1.0.0</version>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.6.6</version>
    </parent>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>

            <exclusions>
                <!--排除默认的Logback日志-->
                                <exclusion>
                                    <groupId>org.springframework.boot</groupId>
                                    <artifactId>spring-boot-starter-logging</artifactId>
                                </exclusion>
            </exclusions>

        </dependency>

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


        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.30</version>
        </dependency>

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

    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                </configuration>

            </plugin>
        </plugins>
    </build>


</project>

二、在resources目录新建log4j2.xml文件：

<Configuration status="error">
    <!--日志存储路径-->
    <Properties>
        <Property name="baseDir" value="d:22\logs"/>
    </Properties>

    <Appenders>
        <Console name="Console" target="SYSTEM_OUT">
            <PatternLayout
                    pattern="[%d{MM:dd HH:mm:ss.SSS}] [%level] [%logger{36}] - %msg%n"/>
        </Console>


        <File name="MyFile" fileName="${baseDir}/app.log">
            <PatternLayout>
                <Pattern>%d %p %c{1.} [%t] %m%n</Pattern>
            </PatternLayout>
        </File>
        <Async name="Async">
            <AppenderRef ref="MyFile"/>
        </Async>

    </Appenders>

    <Loggers>
        <Root level="DEBUG">
            <AppenderRef ref="Console" level="info"/>
            <AppenderRef ref="Async"/>
        </Root>
    </Loggers>

</Configuration>

三、在代码中使用日志记录：

package cn.edu.tju.controller;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import java.util.Date;

@RestController
public class TestController2 {
    Logger logger= LoggerFactory.getLogger(TestController2.class);

    @RequestMapping("/test")
    public String getInfo(){
        logger.info("this is test info......");
        logger.error("this is test error......");
        return new Date().toString();
    }
}