log4j打印mybatis日志

1 pom.xml添加引用：以下三个都要

<dependency>
  <groupId>org.slf4j</groupId>
  <artifactId>slf4j-log4j12</artifactId>
  <version>1.7.25</version>
</dependency>
<dependency>
  <groupId>log4j</groupId>
  <artifactId>log4j</artifactId>
  <version>1.2.17</version>
</dependency>
<dependency>
  <groupId>org.bgee.log4jdbc-log4j2</groupId>
  <artifactId>log4jdbc-log4j2-jdbc4.1</artifactId>
  <version>1.16</version>
</dependency>

2 设置mybatis的配置文件 mybatis-config.xml

<settings>
    <!--打印日志到slf4j-->
    <setting name="logImpl" value="SLF4J"></setting>
</settings>

3 log4j的属性要注意日志级别是DEBUG,尤其是下面第二句，我没注意将INFO修改成DEBUG，日志没打印出来

log4j.rootLogger=DEBUG,file
log4j.appender.file.Threshold=DEBUG