mybatis-全局配置文件-mybatis-config.xml-settings-4

mapUnderscoreToCamelCase

是否开启驼峰命名：
如果开启驼峰命名，若数据库中表的字段为last_name,java类中属性的名为lastName,那么mybatis会自动将查询结果映射到lastName中

mybatis-config.xml

<settings>        <setting name="mapUnderscoreToCamelCase" value="true"/>    </settings>

Employee

public class Employee {    private int id;    private String lastName;    private String email;    private String gender;    ...}