Spring Boot 集成 MapStruct 实现类型转换

在项目中经常会用到DO,BO,DTO,VO等对象的相互转化，这就需要一个高效通用的转化工具，毕竟每个字段get/set方法会很麻烦。

MapStruct 就是这样的一个属性映射工具，只需要定义一个 Mapper 接口，MapStruct就会自动实现这个映射接口，避免了复杂繁琐的映射实现。MapStruct官网地址： http://mapstruct.org/。

本文主要实现Spring Boot 2.0 与 MapStruct 的整合。

一、添加依赖

        <dependency>
            <groupId>org.mapstruct</groupId>
            <artifactId>mapstruct</artifactId>
            <version>1.3.1.Final</version>
        </dependency>
        <dependency>
            <groupId>org.mapstruct</groupId>
            <artifactId>mapstruct-processor</artifactId>
            <version>1.3.1.Final</version>
        </dependency>

二、 编写转换Mapper

VO对象：

package pers.simon.boot.validator.po;

import io.swagger.annotations.ApiModel;
import io.swagger.annotations.ApiModelProperty;
import lombok.Data;
import pers.simon.boot.validator.annotate.Create;
import pers.simon.boot.validator.annotate.IdCard;
import pers.simon.boot.validator.annotate.Update;

import javax.validation.constraints.*;
import java.util.Date;

/**
 * @author simon
 * @date 2019/12/10 10:28
 */
@ApiModel(description = "用户信息表单")
@Data
public class UserVo {

    @ApiModelProperty(value = "用户ID", name = "userId", required = true, example = "123")
    @Null(message = "用户ID必须为空",groups = Create.class)
    @NotBlank(message = "用户ID不能为空",groups = Update.class)
    private String userId;

    @ApiModelProperty(value = "用户名称", name = "userName", required = true, example = "admin")
    @NotBlank(message = "用户名不能为空")
    private String userName;

    @ApiModelProperty(value = "生日", name = "birthday", required = true, example = "2019-11-02")
    @Past(message = "生日必须为过去日期")
    @NotNull(message = "生日不能为空")
    private Date birthday;

    @ApiModelProperty(value = "年龄", name = "age", required = true, example = "11", dataType = "int")
    @Min(value = 10,message = "年龄必须大于10")
    @Max(value = 30,message = "年龄必须小于30")
    @NotNull(message = "年龄不能为空")
    private Integer age;

    @ApiModelProperty(value = "邮箱", name = "email", required = true, example = "11@qq.com")
    @NotBlank(message = "邮箱不能为空")
    @Email(message = "邮箱格式错误")
    private String email;

    @ApiModelProperty(value = "手机号", name = "phone", required = true, example = "12345678900")
    @NotNull(message = "手机号不能为空")
    @NotBlank(message = "手机号不能为空")
    @Pattern(regexp ="^[1][3,4,5,6,7,8,9][0-9]{9}$", message = "手机号格式有误")
    @Max(value = 11,message = "手机号只能为11位")
    @Min(value = 11,message = "手机号只能为11位")
    private String phone;

    @ApiModelProperty(value = "身份证号", name = "idCard", required = true, example = "12345678900")
    @NotBlank(message = "身份证不能为空")
    @IdCard(message = "身份证不合法")
    private String idCard;
}

DTO对象：

package pers.simon.boot.validator.po;

import io.swagger.annotations.ApiModelProperty;
import lombok.Data;
import pers.simon.boot.validator.annotate.Create;
import pers.simon.boot.validator.annotate.IdCard;
import pers.simon.boot.validator.annotate.Update;

import javax.validation.constraints.*;
import java.util.Date;

/**
 * @author simon
 * @date 2019/12/12 16:38
 */
@Data
public class UserDto {
    private String userId;

    private String userName;

    private String password;

    private Date birthday;

    private Integer age;

    private String email;

    private String telPhone;

    private String idCard;

    private Date updateTime;
}

转换Mapper

package pers.simon.boot.validator.convert;

import org.mapstruct.Mapper;
import org.mapstruct.Mapping;
import org.mapstruct.Mappings;
import pers.simon.boot.validator.po.UserDto;
import pers.simon.boot.validator.po.UserVo;

import java.time.LocalDateTime;
import java.time.ZoneId;
import java.util.Date;

/**
 * 用户信息
 *
 * @author simon
 * @date 2019/12/12 16:40
 */
@Mapper(componentModel = "spring",imports = {LocalDateTime.class,Date.class, ZoneId.class})//交给spring管理
public interface UserConvert {
    // 用来调用实例 实际开发中可使用注入Spring  不写
    //UserConvert INSTANCE = Mappers.getMapper(UserConvert.class);
    @Mappings({
            @Mapping(target = "updateTime",expression = "java(Date.from( LocalDateTime.now().atZone( ZoneId.systemDefault()).toInstant()))"),
            @Mapping(target = "password",constant = "admin")
    })
    UserDto convert(UserVo userVo);

    @Mapping(target = "phone",source = "telPhone")
    UserVo convert(UserDto userDto);

}

1. 用@org.mapstruct.Mapper（不要跟mybatis注解混淆）标记类，说明这是一个实体类型转换接口
2. 转换Mapper提供了两个转换方法，分别是UserDto--->UserVo和UserVo---->UserDto
3. componentModel = "spring" 指定 将转换Mapper交给Spring 管理，可实现spring bean 注入
4. imports 用于导入Java 表达式所需要的类，expression 接收一个 java() 包括的表达式
5. source 代表转换的源，target 代表转换的目标
6. MapStruct 最终调用的是 setter 和 getter 方法，而非反射
7. 对常量赋值不能指定 source 属性，@Mapping(target = "password",constant = "admin")

三、测试类

package pers.simon.boot.validator.convert;

import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;
import pers.simon.boot.validator.po.UserDto;
import pers.simon.boot.validator.po.UserVo;
import pers.simon.boot.validator.utils.JsonUtil;

import java.util.Date;

/**
 * @author simon
 * @date 2019/12/12 16:56
 */
@RunWith(SpringRunner.class)
@SpringBootTest
public class UserConvertTest {

    private UserDto userDto;
    private UserVo userVo;

    @Autowired
    private UserConvert userConvert;

    @Before
    public void setUp() throws Exception {
        userDto = new UserDto();
        userDto.setUserId("1111");
        userDto.setUserName("admin");
        userDto.setPassword("password");
        userDto.setEmail("11@qq.com");
        userDto.setTelPhone("12345678900");
        userDto.setAge(12);
        userDto.setBirthday(new Date());
        userDto.setIdCard("123321");
        userDto.setUpdateTime(new Date());

        userVo = new UserVo();
        userVo.setUserId("1111");
        userVo.setUserName("admin");
        userVo.setEmail("11@qq.com");
        userVo.setAge(12);
        userVo.setBirthday(new Date());
        userVo.setIdCard("123321");
    }

    @Test
    public void convert() {
        UserVo convert = userConvert.convert(userDto);
        System.out.println(JsonUtil.toJsonString(convert));
    }

    @Test
    public void testConvert() {
        UserDto convert = userConvert.convert(userVo);
        System.out.println(JsonUtil.toJsonString(convert));
    }
}