Mapstruct典型用例

1. 测试入口：

package com.c2f.hbos.mcc;

import com.alibaba.fastjson.JSON;
import lombok.AllArgsConstructor;
import lombok.Builder;
import lombok.Data;
import lombok.Getter;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.mapstruct.Mapper;
import org.mapstruct.Mapping;
import org.mapstruct.Mappings;
import org.mapstruct.Named;
import org.mapstruct.factory.Mappers;
import org.springframework.test.context.junit4.SpringRunner;

import java.time.LocalDateTime;
import java.util.Arrays;
import java.util.List;

@RunWith(SpringRunner.class)
public class MapStructTest {

    /**
     * 1.单个对象测试
     */
    @Test
    public void po2DtoTest() {
        UserPO po = UserPO.builder()
                .id(1L)
                .name("yang")
                .gender(Gender.MAN)
                .birthday(LocalDateTime.now())
                .build();

        UserDTO dto = UserStructMapper.INSTANCE.po2Dto(po);
        System.err.println(JSON.toJSON(dto));
    }

    /**
     * 2.集合测试
     */
    @Test
    public void po2DtoListTest() {
        UserPO po = UserPO.builder()
                .id(1L)
                .name("yang")
                .gender(Gender.MAN)
                .birthday(LocalDateTime.now())
                .build();
        List<UserPO> poList = Arrays.asList(po);
        List<UserDTO> dtoList = UserStructMapper.INSTANCE.po2DtoList(poList);
        dtoList.forEach(it -> {
            System.err.println(JSON.toJSON(it));
        });
    }

    /**
     * 3.多合一测试
     */
    @Test
    public void personAndAnimal2DtoTest() {
        UserDTO dto = UserStructMapper.INSTANCE.personAndAnimal2Dto(new Person("杨"), new Animal(11L));
        System.err.println(JSON.toJSON(dto));
    }

}

2. Mapstruct工具类：

@Mapper
interface UserStructMapper {

    UserStructMapper INSTANCE = Mappers.getMapper(UserStructMapper.class);

    /**
     * 1.单个对象转换
     *
     * @param po
     * @return
     */
    @Mappings({
            @Mapping(constant = "cn_zh", target = "locale"),
            @Mapping(source = "gender", target = "genderCode", qualifiedByName = "toCode"),
            @Mapping(source = "birthday", target = "birthday", dateFormat = "yyyy-MM-dd HH:mm:ss")
    })
    UserDTO po2Dto(UserPO po);

    /**
     * 2.集合转换（自动引用单个对象转换）
     *
     * @param poList
     * @return
     */
    List<UserDTO> po2DtoList(List<UserPO> poList);

    /**
     * 3.多对象合并为一个对象
     *
     * @param person
     * @param animal
     * @return
     */
    @Mappings({
            @Mapping(source = "animal.id", target = "id"),
            @Mapping(source = "person.name", target = "name")
    })
    UserDTO personAndAnimal2Dto(Person person, Animal animal);

    /**
     * 声明从编号到枚举对象的转换
     *
     * @param code
     * @return
     */
    @Named("fromCode")
    default Gender fromCode(String code) {
        return Gender.valueOf(code);
    }

    /**
     * 声明从枚举对象到编号的转换
     *
     * @param gender
     * @return
     */
    @Named("toCode")
    default String toCode(Gender gender) {
        return gender.getCode();
    }

}

3. Pojo类：

@Getter
enum Gender {

    /**
     * 男
     */
    MAN("0", "男"),

    /**
     * 女
     */
    WOMAN("1", "女");

    private String code;

    private String name;

    Gender(String code, String name) {
        this.code = code;
        this.name = name;
    }

}

@Data
@Builder
class UserPO {

    private Long id;

    private String name;

    private LocalDateTime birthday;

    private Gender gender;
}

@Data
class UserDTO {

    private Long id;

    private String name;

    private LocalDateTime birthday;

    private String genderCode;

    private String locale;
}

@Data
@AllArgsConstructor
class Person {

    private String name;

}

@Data
@AllArgsConstructor
class Animal {

    private Long id;

}