log4j2日志输出益处：西橡胶与 log4j 易于读取日志输出内容,且不需要保存到日志文件夹中，节约内存空间！！！
1.....pom.xml 需要导入的jar包：
1 <!--日志--> 2 <dependency> 3 <groupId>log4j</groupId> 4 <artifactId>log4j</artifactId> 5 <version>1.2.17</version> 6 </dependency> 7 <dependency> 8 <groupId>org.apache.logging.log4j</groupId> 9 <artifactId>log4j-api</artifactId> 10 <version>2.10.0</version> 11 </dependency> 12 <dependency> 13 <groupId>org.apache.logging.log4j</groupId> 14 <artifactId>log4j-core</artifactId> 15 <version>2.10.0</version> 16 </dependency> 17 <dependency> 18 <groupId>org.apache.logging.log4j</groupId> 19 <artifactId>log4j-jcl</artifactId> 20 <version>2.9.1</version> 21 </dependency> 22 <dependency> 23 <groupId>org.apache.logging.log4j</groupId> 24 <artifactId>log4j-slf4j-impl</artifactId> 25 <version>2.9.1</version> 26 </dependency> 27 <dependency> 28 <groupId>org.apache.logging.log4j</groupId> 29 <artifactId>log4j-web</artifactId> 30 <version>2.9.1</version> 31 </dependency> 32 <dependency> 33 <groupId>org.apache.logging.log4j</groupId> 34 <artifactId>log4j-slf4j-impl</artifactId> 35 <version>2.9.1</version> 36 </dependency> 37 <dependency> 38 <groupId>org.slf4j</groupId> 39 <artifactId>slf4j-api</artifactId> 40 <version>1.7.25</version> 41 </dependency>
2..... log4j2.xml -----文件配置信息
1 <?xml version="1.0" encoding="UTF-8"?> 2 <Configuration status="warn" monitorInterval="30" strict="true" schema="Log4J-V2.2.xsd"> 3 <Appenders> 4 <Console name="Console" target="SYSTEM_OUT"> 5 <!-- 将日志输出到控制台 --> 6 <PatternLayout pattern="%date{yyyy-MM-dd HH:mm:ss.SSS} [%thread] %level [%C{36}.%M] - %msg%n"/> 7 </Console> 8 <!--将日志输出到文件中--> 9 <file name="myLogFile" fileName="d:/log/ssm.log" append="true"> 10 <PatternLayout pattern="%date{yyyy-MM-dd HH:mm:ss.SSS} [%thread] %level [%C{36}.%M] - %msg%n"/> 11 </file> 12 </Appenders> 13 14 <Loggers> 15 <!-- 全局配置 --> 16 <root level="info"> 17 <!--普通日志要在哪里显示--> 18 <appenderRef ref="Console"/> 19 <appender-ref ref="myLogFile"/> 20 </root> 21 22 <!-- 业务层日志 --> 23 <logger name="com.itheima.service" level="debug" additivity="false"> 24 <appender-ref ref="Console"/> 25 <appender-ref ref="myLogFile"/> 26 </logger> 27 28 <!-- 持久层日志 --> 29 <logger name="com.itheima.dao" level="debug" additivity="false"> 30 <appender-ref ref="Console"/> 31 <appender-ref ref="myLogFile"/> 32 </logger> 33 <!-- 事务日志 --> 34 <logger name="org.springframework.jdbc" level="debug" additivity="false"> 35 <appender-ref ref="Console"/> 36 <appender-ref ref="myLogFile"/> 37 </logger> 38 </Loggers> 39 40 41 </Configuration>