springboot配置log4j2

部分内容参考：
log4j2.yml配置的文章，很具体，可参考
一个log4j.xml配置的文章（可以参考）

1.引入相关的依赖

<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>


<!-- 包含 mvc,aop 等jar资源 -->
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-web</artifactId>
    <exclusions>
        <!-- 切换log4j2日志读取 -->
        <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-test</artifactId>
    <scope>test</scope>
</dependency>

<!-- 配置 log4j2 -->
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-log4j2</artifactId>
</dependency>
<!-- 加上这个才能辨认到log4j2.yml文件 -->
<dependency>
    <groupId>com.fasterxml.jackson.dataformat</groupId>
    <artifactId>jackson-dataformat-yaml</artifactId>
</dependency>

注意
一定要注意项目中原本的依赖，可能会有冲突，因为使用log4j2依赖一定要排除原本项目中的log4j、logback相关依赖。
我就在此处一直报错，但是最后也不知道哪里错了。。

如果一直报错，如下代码所示。就在右侧maven框中，将项目clean再install一下。

SLF4J: Class path contains multiple SLF4J bindings.
SLF4J: Found binding in [jar:file:/C:/Users/Zll/.m2/repository/ch/qos/logback/logback-classic/1.2.6/logback-classic-1.2.6.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding in [jar:file:/C:/Users/Zll/.m2/repository/org/apache/logging/log4j/log4j-slf4j-impl/2.14.1/log4j-slf4j-impl-2.14.1.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: See http://www.slf4j.org/codes.html#multiple_bindings for an explanation.
SLF4J: Actual binding is of type [ch.qos.logback.classic.util.ContextSelectorStaticBinder]

2.配置相应的log4j2.yml及application.yml文件

log4j2.yml：
注意log4j2的配置文件中的文件存储地址是由log.path的value值决定的。如果value值没有写具体哪个盘，就默认在当前项目路径中创建

# 共有8个级别，按照从低到高为：ALL < TRACE < DEBUG < INFO < WARN < ERROR < FATAL < OFF。

Configuration:
  status: warn
  monitorInterval: 30

  Properties: # 定义全局变量
    Property: # 缺省配置（用于开发环境）。其他环境需要在VM参数中指定，如下：
      #测试：-Dlog.level.console=warn -Dlog.level.xjj=trace
      #生产：-Dlog.level.console=warn -Dlog.level.xjj=info
      - name: log.level.console
        value: info
      - name: log.path
        value: logs/${project.name}_log
      - name: project.name
        value: opendoc
      - name: log.pattern
        value: "%d{yyyy-MM-dd HH:mm:ss.SSS} -%5p ${PID:-} [%15.15t] %-30.30C{1.} : %m%n"

  Appenders:
    Console:  #输出到控制台
      name: CONSOLE
      target: SYSTEM_OUT
      PatternLayout:
        pattern: ${log.pattern}
    #   启动日志
    RollingFile:
      - name: ROLLING_FILE
        fileName: ${log.path}/${project.name}.log
        filePattern: "${log.path}/historyRunLog/$${date:yyyy-MM}/${project.name}-%d{yyyy-MM-dd}-%i.log.gz"
        PatternLayout:
          pattern: ${log.pattern}
        Filters:
          #        一定要先去除不接受的日志级别，然后获取需要接受的日志级别
          ThresholdFilter:
            - level: error
              onMatch: DENY
              onMismatch: NEUTRAL
            - level: info
              onMatch: ACCEPT
              onMismatch: DENY
        Policies:
          TimeBasedTriggeringPolicy:  # 按天分类
            modulate: true
            interval: 1
        DefaultRolloverStrategy:     # 文件最多100个
          max: 100
      #   平台日志
      - name: PLATFORM_ROLLING_FILE
        ignoreExceptions: false
        fileName: ${log.path}/platform/${project.name}_platform.log
        filePattern: "${log.path}/platform/$${date:yyyy-MM}/${project.name}-%d{yyyy-MM-dd}-%i.log.gz"
        PatternLayout:
          pattern: ${log.pattern}
        Policies:
          TimeBasedTriggeringPolicy:  # 按天分类
            modulate: true
            interval: 1
        DefaultRolloverStrategy:     # 文件最多100个
          max: 100
      #   业务日志
      - name: BUSSINESS_ROLLING_FILE
        ignoreExceptions: false
        fileName: ${log.path}/bussiness/${project.name}_bussiness.log
        filePattern: "${log.path}/bussiness/$${date:yyyy-MM}/${project.name}-%d{yyyy-MM-dd}-%i.log.gz"
        PatternLayout:
          pattern: ${log.pattern}
        Policies:
          TimeBasedTriggeringPolicy:  # 按天分类
            modulate: true
            interval: 1
        DefaultRolloverStrategy:     # 文件最多100个
          max: 100
      #   错误日志
      - name: EXCEPTION_ROLLING_FILE
        ignoreExceptions: false
        fileName: ${log.path}/exception/${project.name}_exception.log
        filePattern: "${log.path}/exception/$${date:yyyy-MM}/${project.name}-%d{yyyy-MM-dd}-%i.log.gz"
        ThresholdFilter:
          level: error
          onMatch: ACCEPT
          onMismatch: DENY
        PatternLayout:
          pattern: ${log.pattern}
        Policies:
          TimeBasedTriggeringPolicy:  # 按天分类
            modulate: true
            interval: 1
        DefaultRolloverStrategy:     # 文件最多100个
          max: 100
      #   DB 日志
      - name: DB_ROLLING_FILE
        ignoreExceptions: false
        fileName: ${log.path}/db/${project.name}_db.log
        filePattern: "${log.path}/db/$${date:yyyy-MM}/${project.name}-%d{yyyy-MM-dd}-%i.log.gz"
        PatternLayout:
          pattern: ${log.pattern}
        Policies:
          TimeBasedTriggeringPolicy:  # 按天分类
            modulate: true
            interval: 1
        DefaultRolloverStrategy:     # 文件最多100个
          max: 100


  Loggers:
    Root:
      level: info
      AppenderRef:
        - ref: CONSOLE
        - ref: ROLLING_FILE
        - ref: EXCEPTION_ROLLING_FILE
    Logger:
      - name: platform
        level: info
        additivity: false
        AppenderRef:
          - ref: CONSOLE
          - ref: PLATFORM_ROLLING_FILE

      - name: bussiness
        level: info
        additivity: false
        AppenderRef:
          - ref: BUSSINESS_ROLLING_FILE

      - name: exception
        level: debug
        additivity: true
        AppenderRef:
          - ref: EXCEPTION_ROLLING_FILE

      - name: db
        level: info
        additivity: false
        AppenderRef:
          - ref: DB_ROLLING_FILE


  #    监听具体包下面的日志
  #    Logger: # 为com.xjj包配置特殊的Log级别，方便调试
  #      - name: com.xjj
  #        additivity: false
  #        level: ${sys:log.level.xjj}
  #        AppenderRef:
  #          - ref: CONSOLE
  #          - ref: ROLLING_FILE

application.xml：（注意将原本springboot文件中内置日志的相关配置清除）
application.xml：

logging:
  config: classpath:log4j2.yml

3.编写相应的测试接口

引入相应包：

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

//定义logger：
protected final Logger logger = LoggerFactory.getLogger(this.getClass());

//在Controller中随便写个测试接口，使用第一种第二种都可
//第一种，没有定义相应的配置工具类，简单使用
@GetMapping(value="/test")
	public String test(){
		logger.debug("debug ****************************");
		logger.info("info ****************************");
		logger.warn("warn ****************************");
		logger.error("error ****************************");
		return "success";
	}
	
	//第二种，定义了相应的log枚举类、工具类，具体可参见引用的文章，很具体。
	@GetMapping("/helloworld")
	public String helloworld() throws Exception{
		Logger log = LogUtils.getExceptionLogger();
		Logger log1 = LogUtils.getBussinessLogger();
		Logger log2 = LogUtils.getDBLogger();
		userService.findUsers(0,10,"");
		log.error("getExceptionLogger===日志测试");
		log1.info("getBussinessLogger===日志测试");
		log2.debug("getDBLogger===日志测试");
		return "helloworld";
	}

4.在postman中进行测试即可

如图示即可。
如果觉得代码不完整，参考相应的参考文章（更为具体）

最后，感觉log4j2配置完以后看不到数据库表调用的SQL语句。（也可能我还没配置到）没有springboot内置的日志好，那个直接改为debug级别就可以显示sql及库表调用的情况。

# 调试时使用
  Loggers:
    Root:
      level: info
      AppenderRef:
        - ref: CONSOLE
    Logger: #单独设置某些包的输出级别
      - name: com.thzh #复数加上-
        additivity: false #去除重复的log
        level: debug
        AppenderRef:
          - ref: CONSOLE #复数加上-
          - ref: ROLLING_FILE #复数加上-

具体为什么这么配置不太清楚，慢慢学习。