解決方法:
1、把mapper.xml放到src\main\resource文件夾下即可
2、在pom.xml下加個配置:(可直接複製,如需修改)
<build>
<resource>
<directory>src/main/java</directory>
<includes>
<include>**/*.xml</include>
</includes>
</resource>
</resources>
</build>