错误信息：
Failed to execute goal org.apache.maven.plugins:maven-surefire-plugin:2.22.2:test (default-test) on project web-class-book: There are test failures.
Please refer to D:\idea_workspace\web-class-book\target\surefire-reports for the individual test results.
Please refer to dump files (if any exist) [date].dump, [date]-jvmRun[N].dump and [date].dumpstream.
原因：
UserMapper.java配置了@Select，但UserMapper.xml也配置了<Select>导致的。
两个地方的代码重复了。取其一即可。
```
@Mapper
public interface UserMapper {
@Select("select * from user")
public List list();
}
```
```
<select id="list" resultType="com.demo.User">
select* from user;
</select>
```
