springboot中将logback切换为log4j2

雨点打透心脏的1/2处 2024-03-16 07:12 35阅读 0赞

前言  
springboot默认使用logback作为日志记录框架，常见的日志记录框架有log4j、logback、log4j2。这篇文章我们来学习怎样将logbak替换为log4j2。  
一、为什么使用log4j2？  
我们在项目中经常使用一个叫SLF4J的依赖，它是做什么的呢？

slf4j是对所有日志框架制定的一种规范、标准、接口，并不是一个框架的具体的实现，它的接口并不能独立使用，需要和具体的日志框架实现配合使用（如log4j、logback、log4j2）。

log4j是apache实现的一个开源日志组件。  
logback同样是由log4j的作者设计完成的，拥有更好的特性，用来取代log4j的一个日志框架，是slf4j的原生实现。  
Log4j2是log4j 1.x和logback的改进版，性能最高。  
log4j2异步记录日志使用了disruptor框架，性能得到了提高，记录日志的流程如下：

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTE5NDM1MzQ_size_16_color_FFFFFF_t_70]  
几种日志框架的性能测试对比如下：

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTE5NDM1MzQ_size_16_color_FFFFFF_t_70 1]

## 二、使用步骤 ##

### 1.引入库 ###

gradle：

//引入log4j2
    api 'org.springframework.boot:spring-boot-starter-log4j2'
    api "com.lmax:disruptor:3.4.4"
        
    //删除logback依赖
    configurations {
        
        api.exclude group: 'org.springframework.boot', module: 'spring-boot-starter-logging'
        api.exclude group: 'ch.qos.logback', module: 'logback-access'
        api.exclude group: 'ch.qos.logback', module: 'logback-classic'
        api.exclude group: 'ch.qos.logback', module: 'logback-core'
    }

maven:

<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>
    
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-log4j2</artifactId>
    </dependency>
    
    <dependency>
        <groupId>com.lmax</groupId>
        <artifactId>disruptor</artifactId>
        <version>3.4.4</version>
    </dependency>

### 2.编写log4j2配置文件 ###

在application.properties中引入配置文件

logging.config=classpath:log4j2-spring.xml

在resources下添加log4j2-spring.xml配置文件  
以下是我在项目中的配置，注意的是使用AsyncLogger才会使用disruptor提高性能。如果使用的AsyncAppender，则使用的是类似logback一样的队列的方式做异步记录。

<?xml version="1.0" encoding="UTF-8"?>
    
    
    
    <configuration status="error" monitorInterval="30">
        
    
        
        <properties>
            
            
            <property name="LOG_PATTERN" value="%d{yyyy-MM-dd HH:mm:ss.SSS} [%t] %-5level [%logger{50}:%L] - %msg%n"/>
            <property name="LOG_CONSOLE_PATTERN" value="%style{%d{ISO8601}}{bright,green} %highlight{%-5level} [%style{%t}{bright,blue}] %style{%C{}}{bright,yellow}: %msg%n%style{%throwable}{red}"/>
            
            <property name="FILE_PATH" value="logs"/>
            <property name="FILE_NAME" value="newframe"/>
        </properties>
    
        <Appenders>
            
            <Console name="consoleAppender" target="SYSTEM_OUT">
                
                <PatternLayout pattern="${LOG_PATTERN}" charset="UTF-8"/>
            </Console>
    
            
            
            <RollingFile name="infoFileAppender"
                         fileName="${FILE_PATH}/${FILE_NAME}/log_info.log"
                         filePattern="${FILE_PATH}/${FILE_NAME}/log-info-%d{yyyy-MM-dd}_%i.log.gz"
                         append="true">
                
                <PatternLayout pattern="${LOG_PATTERN}" charset="UTF-8"/>
                <Filters>
                    
                    <ThresholdFilter level="warn" onMatch="DENY" onMismatch="NEUTRAL" />
                    <ThresholdFilter level="info" onMatch="ACCEPT" onMismatch="DENY"/>
                </Filters>
                <Policies>
                    
                    <TimeBasedTriggeringPolicy interval="1"/>
                    <SizeBasedTriggeringPolicy size="10MB"/>
                </Policies>
    
                
                <DefaultRolloverStrategy max="30">
                    
                    <Delete basePath="${FILE_PATH}/${FILE_NAME}/" maxDepth="2">
                        
                        <IfFileName glob="*.log.gz"/>
                        
                        
                        <IfLastModified age="7d"/>
                    </Delete>
                </DefaultRolloverStrategy>
    
            </RollingFile>
    
            
            
            <RollingFile name="warnFileAppender"
                         fileName="${FILE_PATH}/${FILE_NAME}/log_warn.log"
                         filePattern="${FILE_PATH}/${FILE_NAME}/log-warn-%d{yyyy-MM-dd}_%i.log.gz"
                         append="true">
                
                <PatternLayout pattern="${LOG_PATTERN}" charset="UTF-8"/>
                <Filters>
                    
                    <ThresholdFilter level="error" onMatch="DENY" onMismatch="NEUTRAL" />
                    <ThresholdFilter level="warn" onMatch="ACCEPT" onMismatch="DENY"/>
                </Filters>
                <Policies>
                    
                    <TimeBasedTriggeringPolicy interval="1"/>
                    <SizeBasedTriggeringPolicy size="10MB"/>
                </Policies>
    
                
                <DefaultRolloverStrategy max="30">
                    
                    <Delete basePath="${FILE_PATH}/${FILE_NAME}/" maxDepth="2">
                        
                        <IfFileName glob="*.log.gz"/>
                        
                        
                        <IfLastModified age="7d"/>
                    </Delete>
                </DefaultRolloverStrategy>
    
    
            </RollingFile>
    
            
            
            <RollingFile name="errorFileAppender"
                         fileName="${FILE_PATH}/${FILE_NAME}/log_error.log"
                         filePattern="${FILE_PATH}/${FILE_NAME}/log-error-%d{yyyy-MM-dd}_%i.log.gz"
                         append="true">
                
                <PatternLayout pattern="${LOG_PATTERN}" charset="UTF-8"/>
                <Filters>
                    <ThresholdFilter level="error" onMatch="ACCEPT" onMismatch="DENY"/>
                </Filters>
                <Policies>
                    
                    <TimeBasedTriggeringPolicy interval="1"/>
                    <SizeBasedTriggeringPolicy size="10MB"/>
                </Policies>
    
                
                <DefaultRolloverStrategy max="30">
                    
                    <Delete basePath="${FILE_PATH}/${FILE_NAME}/" maxDepth="2">
                        
                        <IfFileName glob="*.log.gz"/>
                        
                        
                        <IfLastModified age="7d"/>
                    </Delete>
                </DefaultRolloverStrategy>
    
            </RollingFile>
    
    
            
        </Appenders>
    
    
        <Loggers>
            <AsyncLogger name="org.apache.http" level="info" includeLocation="true" additivity="false">
                <AppenderRef ref="infoFileAppender"/>
                <AppenderRef ref="warnFileAppender"/>
                <AppenderRef ref="errorFileAppender"/>
                <AppenderRef ref="consoleAppender"/>
            </AsyncLogger>
            <AsyncLogger name="io.lettuce" level="info" includeLocation="true" additivity="false">
                <AppenderRef ref="infoFileAppender"/>
                <AppenderRef ref="warnFileAppender"/>
                <AppenderRef ref="errorFileAppender"/>
                <AppenderRef ref="consoleAppender"/>
            </AsyncLogger>
            <AsyncLogger name="io.netty" level="info" includeLocation="true" additivity="false">
                <AppenderRef ref="infoFileAppender"/>
                <AppenderRef ref="warnFileAppender"/>
                <AppenderRef ref="errorFileAppender"/>
                <AppenderRef ref="consoleAppender"/>
            </AsyncLogger>
            <AsyncLogger name="org.quartz" level="info" includeLocation="true" additivity="false">
                <AppenderRef ref="infoFileAppender"/>
                <AppenderRef ref="warnFileAppender"/>
                <AppenderRef ref="errorFileAppender"/>
                <AppenderRef ref="consoleAppender"/>
            </AsyncLogger>
            <AsyncLogger name="org.springframework" level="info" includeLocation="true" additivity="false">
                <AppenderRef ref="infoFileAppender"/>
                <AppenderRef ref="warnFileAppender"/>
                <AppenderRef ref="errorFileAppender"/>
                <AppenderRef ref="consoleAppender"/>
            </AsyncLogger>
            <AsyncLogger name="org.springdoc" level="info" includeLocation="true" additivity="false">
                <AppenderRef ref="infoFileAppender"/>
                <AppenderRef ref="warnFileAppender"/>
                <AppenderRef ref="errorFileAppender"/>
                <AppenderRef ref="consoleAppender"/>
            </AsyncLogger>
            <AsyncLogger name="druid.sql" level="info" includeLocation="true" additivity="false">
                <AppenderRef ref="infoFileAppender"/>
                <AppenderRef ref="warnFileAppender"/>
                <AppenderRef ref="errorFileAppender"/>
                <AppenderRef ref="consoleAppender"/>
            </AsyncLogger>
            <AsyncLogger name="io.undertow" level="info" includeLocation="true" additivity="false">
                <AppenderRef ref="infoFileAppender"/>
                <AppenderRef ref="warnFileAppender"/>
                <AppenderRef ref="errorFileAppender"/>
                <AppenderRef ref="consoleAppender"/>
            </AsyncLogger>
            <AsyncLogger name="sun.rmi" level="info" includeLocation="true" additivity="false">
                <AppenderRef ref="infoFileAppender"/>
                <AppenderRef ref="warnFileAppender"/>
                <AppenderRef ref="errorFileAppender"/>
                <AppenderRef ref="consoleAppender"/>
            </AsyncLogger>
            <AsyncLogger name="com.sun.mail" level="info" includeLocation="true" additivity="false">
                <AppenderRef ref="infoFileAppender"/>
                <AppenderRef ref="warnFileAppender"/>
                <AppenderRef ref="errorFileAppender"/>
                <AppenderRef ref="consoleAppender"/>
            </AsyncLogger>
            <AsyncLogger name="javax.management" level="info" includeLocation="true" additivity="false">
                <AppenderRef ref="infoFileAppender"/>
                <AppenderRef ref="warnFileAppender"/>
                <AppenderRef ref="errorFileAppender"/>
                <AppenderRef ref="consoleAppender"/>
            </AsyncLogger>
            <AsyncLogger name="de.codecentric" level="info" includeLocation="true" additivity="false">
                <AppenderRef ref="infoFileAppender"/>
                <AppenderRef ref="warnFileAppender"/>
                <AppenderRef ref="errorFileAppender"/>
                <AppenderRef ref="consoleAppender"/>
            </AsyncLogger>
            <AsyncLogger name="org.hibernate.validator" level="info" includeLocation="true" additivity="false">
                <AppenderRef ref="infoFileAppender"/>
                <AppenderRef ref="warnFileAppender"/>
                <AppenderRef ref="errorFileAppender"/>
                <AppenderRef ref="consoleAppender"/>
            </AsyncLogger>
            <AsyncLogger name="org.mybatis.spring.mapper" level="info" includeLocation="true" additivity="false">
                <AppenderRef ref="infoFileAppender"/>
                <AppenderRef ref="warnFileAppender"/>
                <AppenderRef ref="errorFileAppender"/>
                <AppenderRef ref="consoleAppender"/>
            </AsyncLogger>
            <AsyncLogger name="org.xnio" level="info" includeLocation="true" additivity="false">
                <AppenderRef ref="infoFileAppender"/>
                <AppenderRef ref="warnFileAppender"/>
                <AppenderRef ref="errorFileAppender"/>
                <AppenderRef ref="consoleAppender"/>
            </AsyncLogger>
            <AsyncLogger name="springfox" level="info" includeLocation="true" additivity="false">
                <AppenderRef ref="infoFileAppender"/>
                <AppenderRef ref="warnFileAppender"/>
                <AppenderRef ref="errorFileAppender"/>
                <AppenderRef ref="consoleAppender"/>
            </AsyncLogger>
            <AsyncLogger name="com.baomidou" level="info" includeLocation="true" additivity="false">
                <AppenderRef ref="infoFileAppender"/>
                <AppenderRef ref="warnFileAppender"/>
                <AppenderRef ref="errorFileAppender"/>
                <AppenderRef ref="consoleAppender"/>
            </AsyncLogger>
            <AsyncLogger name="io.micrometer.core" level="info" includeLocation="true" additivity="false">
                <AppenderRef ref="infoFileAppender"/>
                <AppenderRef ref="warnFileAppender"/>
                <AppenderRef ref="errorFileAppender"/>
                <AppenderRef ref="consoleAppender"/>
            </AsyncLogger>
            <AsyncLogger name="Validator" level="info" includeLocation="true" additivity="false">
                <AppenderRef ref="infoFileAppender"/>
                <AppenderRef ref="warnFileAppender"/>
                <AppenderRef ref="errorFileAppender"/>
                <AppenderRef ref="consoleAppender"/>
            </AsyncLogger>
            <AsyncLogger name="org.neo4j" level="info" includeLocation="true" additivity="false">
                <AppenderRef ref="infoFileAppender"/>
                <AppenderRef ref="warnFileAppender"/>
                <AppenderRef ref="errorFileAppender"/>
                <AppenderRef ref="consoleAppender"/>
            </AsyncLogger>
            <AsyncLogger name="org.apache.zookeeper" level="info" includeLocation="true" additivity="false">
                <AppenderRef ref="infoFileAppender"/>
                <AppenderRef ref="warnFileAppender"/>
                <AppenderRef ref="errorFileAppender"/>
                <AppenderRef ref="consoleAppender"/>
            </AsyncLogger>
            <AsyncLogger name="org.apache.curator" level="info" includeLocation="true" additivity="false">
                <AppenderRef ref="infoFileAppender"/>
                <AppenderRef ref="warnFileAppender"/>
                <AppenderRef ref="errorFileAppender"/>
                <AppenderRef ref="consoleAppender"/>
            </AsyncLogger>
            <AsyncLogger name="oshi.util" level="info" includeLocation="true" additivity="false">
                <AppenderRef ref="infoFileAppender"/>
                <AppenderRef ref="warnFileAppender"/>
                <AppenderRef ref="errorFileAppender"/>
                <AppenderRef ref="consoleAppender"/>
            </AsyncLogger>
            <AsyncLogger name="net.javacrumbs" level="info" includeLocation="true" additivity="false">
                <AppenderRef ref="infoFileAppender"/>
                <AppenderRef ref="warnFileAppender"/>
                <AppenderRef ref="errorFileAppender"/>
                <AppenderRef ref="consoleAppender"/>
            </AsyncLogger>
            <AsyncLogger name="com.atomikos" level="info" includeLocation="true" additivity="false">
                <AppenderRef ref="infoFileAppender"/>
                <AppenderRef ref="warnFileAppender"/>
                <AppenderRef ref="errorFileAppender"/>
                <AppenderRef ref="consoleAppender"/>
            </AsyncLogger>
    
            <AsyncRoot level="debug" includeLocation="true" additivity="false">
                <AppenderRef ref="infoFileAppender"/>
                <AppenderRef ref="warnFileAppender"/>
                <AppenderRef ref="errorFileAppender"/>
                <AppenderRef ref="consoleAppender"/>
            </AsyncRoot>
        </Loggers>
    
        
        
        
    
    
    </configuration>

### **总结** ###

log4j2使用了两种方式记录日志：AsyncAppender和AsyncLogger，上面我们的配置采用了AsyncLogger，性能最佳。  
1、AsyncAppender使用队列异步记录日志，但是一旦队列已满，appender线程需要等待。  
2、AsyncLogger是采用Disruptor，通过环形队列无阻塞队列作为缓冲，多生产者多线程的竞争是通过CAS实现，无锁化实现，可以降低极端大的日志量时候的延迟尖峰，Disruptor 可是号称一个线程里每秒处理600万订单的高性能队列。

下图是官方给出的性能对比：

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTE5NDM1MzQ_size_16_color_FFFFFF_t_70 2]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTE5NDM1MzQ_size_16_color_FFFFFF_t_70]: https://image.dandelioncloud.cn/pgy_files/images/2024/03/16/747d9680671246d8847df0e9511a8da4.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTE5NDM1MzQ_size_16_color_FFFFFF_t_70 1]: https://image.dandelioncloud.cn/pgy_files/images/2024/03/16/2cb587d4276542dc8a27b6589b557d9c.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTE5NDM1MzQ_size_16_color_FFFFFF_t_70 2]: https://image.dandelioncloud.cn/pgy_files/images/2024/03/16/07bb2573caf54fbea0d84845927af7ae.png