将 SpringBoot 默认的 Logback 切换为 log4j 日志框架。 <br/> 步骤如下： **1. 把logback排除并引入slf4j-log4j** ```xml <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> <exclusions> <exclusion> <artifactId>logback-classic</artifactId> <groupId>ch.qos.logback</groupId> </exclusion> </exclusions> </dependency> <dependency> <groupId>org.slf4j</groupId> <artifactId>slf4j-log4j12</artifactId> <version>1.7.30</version> <scope>test</scope> </dependency> </dependencies> ``` **2. 项目添加log4j的配置文件`resources/log4j.properties`** ```properties ### set log levels ### log4j.rootLogger = debug , stdout , D , E ### 输出到控制台 ### log4j.appender.stdout = org.apache.log4j.ConsoleAppender log4j.appender.stdout.Target = System.out log4j.appender.stdout.layout = org.apache.log4j.PatternLayout log4j.appender.stdout.layout.ConversionPattern = %d{ABSOLUTE} ===== %5p %c{ 1 }:%L - %m%n #### 输出到日志文件 ### #log4j.appender.D = org.apache.log4j.DailyRollingFileAppender #log4j.appender.D.File = logs/log.log #log4j.appender.D.Append = true #log4j.appender.D.Threshold = DEBUG ## 输出DEBUG级别以上的日志 #log4j.appender.D.layout = org.apache.log4j.PatternLayout #log4j.appender.D.layout.ConversionPattern = %-d{yyyy-MM-dd HH:mm:ss} [ %t:%r ] - [ %p ] %m%n # #### 保存异常信息到单独文件 ### #log4j.appender.D = org.apache.log4j.DailyRollingFileAppender #log4j.appender.D.File = logs/error.log ## 异常日志文件名 #log4j.appender.D.Append = true #log4j.appender.D.Threshold = ERROR ## 只输出ERROR级别以上的日志!!! #log4j.appender.D.layout = org.apache.log4j.PatternLayout #log4j.appender.D.layout.ConversionPattern = %-d{yyyy-MM-dd HH:mm:ss} [ %t:%r ] - [ %p ] %m%n ```