SpringBoot2.3整合MapStruct实现Java bean映射

MapStruct 是一个代码生成器，它基于约定优于配置方法极大地简化了 Java bean 类型之间映射的实现。方便pojo、vo、dto与实体类之间的相互转换。更多详情请参阅官网
优缺点

• MapStruct在编译的时候生成映射的代码，如果有错误会在编译时就发现
• 底层使用get/set方法，而非反射方式，执行时效率更快
• 可以实现深拷贝，修改新对象时不会对老对象产生影响
• 类型更加安全，只能映射相互映射的对象和属性，可以进行自定义的类型和字段映射
• 需要额外新增一个接口或者抽象类

    8
    8
    1.4.2.Final
    1.18.20
    0.2.0



    
        org.springframework.boot
        spring-boot-starter-web
    
    
        org.mapstruct
        mapstruct
        ${mapstruct.version}
    
    
        org.projectlombok
        lombok
        provided
    
    
        org.springframework.boot
        spring-boot-starter-test
        test
    



    
        
            org.apache.maven.plugins
            maven-compiler-plugin
            3.8.1
            
                1.8
                1.8
                
                    
                        org.mapstruct
                        mapstruct-processor
                        ${mapstruct.version}
                    
                    
                        org.projectlombok
                        lombok
                        ${lombok.version}
                    
                    
                        org.projectlombok
                        lombok-mapstruct-binding
                        ${lombok-mapstruct.version}
                    
                
            
        
    

@Getter
@Setter
@Builder
@ToString
@NoArgsConstructor
@AllArgsConstructor
public class SysUserInfo {

    
    private Long id;

    
    private String userName;

    
    private SexEnum sex;

    
    private String email;

    
    private String phonenumber;

    
    private String avatar;

    
    private Integer status;

    
    private BigDecimal salary;

    
    private String createUser;

    
    private LocalDateTime createTime;

    
    private String updateUser;
}

@Getter
@Setter
@Builder
@ToString
@NoArgsConstructor
@AllArgsConstructor
public class UserVo {

    
    private String id;

    
    private String userName;

    
    private String password;

    
    private String sex;

    
    private String email;

    
    private String phone;

    
    private String avatar;

    
    private String status;

    
    private String salary;

    
    private String createUser;

    
    private String createTime;

    
    private String updateUser;

    
    private String updateTime;
}

@Mapper
public interface SysUserInfoMapper {

    SysUserInfoMapper INFO_MAPPER = Mappers.getMapper(SysUserInfoMapper.class);

    @Mapping(target = "id", defaultValue = "1")
    @Mapping(target = "password", ignore = true)
    @Mapping(source = "phonenumber", target = "phone")
    @Mapping(source = "sex.value", target = "sex")
    @Mapping(target = "status", constant = "正常")
    @Mapping(target = "salary", numberFormat = "#.00")
    @Mapping(target = "createTime", dateFormat = "yyyy-MM-dd HH:mm:ss")
    @Mapping(source = "userInfo", target = "updateTime", qualifiedByName = "now")
    UserVo map(SysUserInfo userInfo);

    @Named("now")
    default LocalDateTime now(Object source) {
        return LocalDateTime.now();
    }
}

@SpringBootTest
public class MapStructApplicationTest {

    @Test
    void userTest() {
        SysUserInfo userInfo = SysUserInfo.builder()
                .id(1L)
                .userName("zhangsan")
                .sex(SexEnum.MALE)
                .email("zhangsan@163.com")
                .status(0)
                .salary(new BigDecimal(12000))
                .phonenumber("13898767890")
                .createUser("admin")
                .createTime(LocalDateTime.now())
                .updateUser("admin")
                .build();
        UserVo userVo = SysUserInfoMapper.INFO_MAPPER.map(userInfo);
        System.out.println(userVo.toString());
        Assertions.assertNotNull(userVo);
    }
}

Mapper接口可以使用工厂方法注入，也可以使用依赖注入方式，如下所示：

@Mapper(componentModel = "spring")
public interface SysUserInfoMapper {

    @Mapping(target = "id", defaultValue = "1")
    @Mapping(target = "password", ignore = true)
    @Mapping(source = "phonenumber", target = "phone")
    @Mapping(source = "sex.value", target = "sex")
    @Mapping(target = "status", constant = "正常")
    @Mapping(target = "salary", numberFormat = "#.00")
    @Mapping(target = "createTime", dateFormat = "yyyy-MM-dd HH:mm:ss")
    @Mapping(source = "userInfo", target = "updateTime", qualifiedByName = "now")
    UserVo map(SysUserInfo userInfo);

    @Named("now")
    default LocalDateTime now(Object source) {
        return LocalDateTime.now();
    }
}

使用时只需要按照普通接口注入就行
@Mapping注解属性值解释
source：数据源
target：目标对象
defaultValue：用于设置默认值
constant：用于设置常量
numberFormat：用于设置数据格式
dateFormat：用于设置日期格式
qualifiedByName：用于自定义命名

更多使用方法可参阅官网文档
更多示例可参阅官网示例