首先说明版本：

log4j 版本是 第2版beta9，引用jar包

log4j-api-2.0-beta9.jar log4j-core-2.0-beta9.jar

mybatis 是 mybatis-3.2.3

log4j2 配置 如下，命名为 log4j2.xml（log4j2只能用xml或者json，其他命名格式在此不在介绍）将其放在classpath下，内容如下：

<?xml version="1.0" encoding="UTF-8"?>
<configuration status="OFF"> <appenders> <Console name="Console" target="SYSTEM_OUT"> <PatternLayout pattern="%d{HH:mm:ss.SSS} [%t] %-5level %logger{36} - %msg%n"/> </Console> </appenders> <loggers> <logger name="log4j.logger.noModule" level="fatal" additivity="false"><appender-ref ref="Console"/> </logger><logger name="log4j.logger.org.mybatis.jpetstore" level="trace" additivity="false"><appender-ref ref="Console"/> </logger><logger name="log4j.logger.com.opensymphony.xwork2" level="debug" additivity="false"><appender-ref ref="Console"/> </logger><logger name="log4j.logger.com.ibatis" level="trace" additivity="false"><appender-ref ref="Console"/> </logger><logger name="log4j.logger.com.ibatis.common.jdbc.SimpleDataSource" level="debug" additivity="false"><appender-ref ref="Console"/> </logger><logger name="log4j.logger.com.ibatis.common.jdbc.ScriptRunner" level="debug" additivity="false"><appender-ref ref="Console"/> </logger><logger name="log4j.logger.com.ibatis.sqlmap.engine.impl.SqlMapClientDelegate" level="debug" additivity="false"><appender-ref ref="Console"/> </logger><logger name="log4j.logger.org.mybatis" level="debug" additivity="false"><appender-ref ref="Console"/> </logger><logger name="log4j.logger.java.sql" level="debug" additivity="false"><appender-ref ref="Console"/> </logger><logger name="log4j.logger.java.sql.Connection" level="debug" additivity="false"><appender-ref ref="Console"/> </logger><logger name="log4j.logger.java.sql.Statement" level="debug" additivity="false"><appender-ref ref="Console"/> </logger><logger name="log4j.logger.java.sql.PreparedStatement" level="debug" additivity="false"><appender-ref ref="Console"/> </logger><logger name="log4j.logger.java.sql.ResultSet" level="debug" additivity="false"><appender-ref ref="Console"/> </logger><root level="trace"> <appender-ref ref="Console"/> </root> </loggers>
</configuration>

光有这个配置是不行滴，因为mybatis加载日志组件是有顺序的，他会按

• SLF4J

• Apache Commons Logging

• Log4j 2

• Log4j

• JDK logging

的顺序查找。所以，如果在web应用中用了spring之类的框架，他会包含commons-log包，根据优先级，他就不会去用log4j了，所以还得在mybatis配置文件中配置一条语句，如下

<settings><setting name="logImpl" value="LOG4J2"/>
</settings>

然后就可以了

本文出自 “龙之谷” 博客，请务必保留此出处http://sdvdxl.blog.51cto.com/3845763/1319815