目录结构介绍

一：pom依赖

        <dependency>
            <groupId>org.mapstruct</groupId>
            <artifactId>mapstruct</artifactId>
            <version>1.4.2.Final</version>
        </dependency>
        <dependency>
            <groupId>org.mapstruct</groupId>
            <artifactId>mapstruct-processor</artifactId>
            <version>1.4.2.Final</version>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version> 1.18.20</version>
        </dependency>

二：DO对象

@Data
@NoArgsConstructor
@AllArgsConstructor
public class UserDo implements Serializable {
    private static final long serialVersionUID = 6110524897651597826L;

    private int id;

    private String name;

    private int age;

    private String address;

    private String role;

    private Date createDate;

    private Date updateDate;

    private String createUser;

    private  String updateUser;
}

三：Po对象

@Data
@NoArgsConstructor
@AllArgsConstructor
public class UserPo implements Serializable {
    private static final long serialVersionUID = -3055967092435722132L;

    private int id;

    private String name;

    private int age;

    private String address;

    private String role;

    private Date createDate;

    private Date updateDate;

    private String createUser;

    private String updateUser;
}

四：转换工具

BaseMapping

package com.example.demo.utils;

import org.mapstruct.InheritConfiguration;
import org.mapstruct.InheritInverseConfiguration;
import org.mapstruct.MapperConfig;

import java.util.List;
import java.util.stream.Stream;

@MapperConfig
public interface BaseMapping<SOURCE, TARGET> {

    /**
     * 映射同名属性
     */
    TARGET sourceToTarget(SOURCE var1);

    /**
     * 反向，映射同名属性
     */
    @InheritInverseConfiguration(name = "sourceToTarget")
    SOURCE targetToSource(TARGET var1);

    /**
     * 映射同名属性，集合形式
     */
    @InheritConfiguration(name = "sourceToTarget")
    List<TARGET> sourceToTarget(List<SOURCE> var1);

    /**
     * 反向，映射同名属性，集合形式
     */
    @InheritConfiguration(name = "targetToSource")
    List<SOURCE> targetToSource(List<TARGET> var1);

    /**
     * 映射同名属性，集合流形式
     */
    List<TARGET> sourceToTarget(Stream<SOURCE> stream);

    /**
     * 反向，映射同名属性，集合流形式
     */
    List<SOURCE> targetToSource(Stream<TARGET> stream);
}

UserConverter

package com.example.demo.converter;

import com.example.demo.entity.UserDo;
import com.example.demo.po.UserPo;
import com.example.demo.utils.BaseMapping;
import org.mapstruct.Mapper;

/**
 * @Description: do和po互相转换报告集合之前互相转换
 * @Date: 2021/9/23 14:49
 **/
@Mapper(componentModel = "spring")
public interface UserConverter extends BaseMapping<UserDo, UserPo> {
}

五：测试

 /**
     * 注入转换
     */
    @Autowired
    private UserConverter userConverter;
    /**
     * 实现Do映射Po，使用sourceToTarget
     */
    @Test
    void DoConverterPo() {
        UserDo userDo = new UserDo();
        userDo.setId(1);
        userDo.setName("小明");
        userDo.setAge(18);
        userDo.setRole("学生");
        userDo.setCreateDate(new Date());
        userDo.setCreateUser("李白");
        UserPo userPo = userConverter.sourceToTarget(userDo);
        System.out.println("userPo = " + userPo);
        //userPo = UserPo(id=1, name=小明, age=18, address=null, role=学生, createDate=Thu Sep 23 16:28:59 CST 2021, updateDate=null, createUser=李白, updateUser=null)
    }
    /**
     * 实现Po映射Do，使用targetToSource
     */
    @Test
    void PoConverterDo() {
        UserPo userPo = new UserPo();
        userPo.setId(1);
        userPo.setName("小明");
        userPo.setAge(18);
        userPo.setRole("学生");
        userPo.setCreateDate(new Date());
        userPo.setCreateUser("李白");
        UserDo userDo = userConverter.targetToSource(userPo);
        System.out.println("userDo = " + userDo);
        //userDo = UserDo(id=1, name=小明, age=18, address=null, role=学生, createDate=Thu Sep 23 16:31:25 CST 2021, updateDate=null, createUser=李白, updateUser=null)
    }
    /**
     * 实现Dos映射Pos，使用sourceToTarget
     */
    @Test
    void DoListConverterPoList() {
        List<UserDo> userDos = new ArrayList<>();
        UserDo userDo = new UserDo();
        userDo.setId(1);
        userDo.setName("小明");
        userDo.setAge(18);
        userDo.setRole("学生");
        userDo.setCreateDate(new Date());
        userDo.setCreateUser("李白");

        UserDo userDo2 = new UserDo();
        userDo2.setId(2);
        userDo2.setName("大明");
        userDo2.setAge(18);
        userDo2.setRole("学生");
        userDo2.setCreateDate(new Date());
        userDo2.setCreateUser("李白");

        userDos.add(userDo);
        userDos.add(userDo2);
        List<UserPo> userPos = userConverter.sourceToTarget(userDos);
        System.out.println("userPos = " + userPos);
        //userPos =
        // [UserPo(id=1, name=小明, age=18, address=null, role=学生, createDate=Thu Sep 23 16:41:27 CST 2021, updateDate=null, createUser=李白, updateUser=null),
        // UserPo(id=2, name=大明, age=18, address=null, role=学生, createDate=Thu Sep 23 16:41:27 CST 2021, updateDate=null, createUser=李白, updateUser=null)]
    }

六：当对象中有字段不一致的情况时，需要重写方法

@Mapper(componentModel = "spring")
public interface UserConverter extends BaseMapping<UserDo, UserPo> {

    @Mapping(target = "fatherName", source = "userExetend.fatherName")
    @Mapping(target = "motherName", source = "userExetend.motherName")
    @Mapping(target = "xiongDi", source = "brother")
    @Override
    UserPo sourceToTarget(UserDo var1);
}

源码：注：在字段不一致手动映射时，打包失败，错误信息为： Error:(22,12) java: No property named "fatherName" exists in source parameter(s). Did you mean "null"?。 第一位博主也出现过类似问题第二位博主的友情提示我也是有些奇怪，字段都是一样时使用没有任何问题，在这里踩了个坑。 mapstruct版本和lombok版本不一致导致。最后我将lombok版本降低为1.18.12问题就解决了。此种搭配最终解决：

        <dependency>
            <groupId>org.mapstruct</groupId>
            <artifactId>mapstruct</artifactId>
            <version>1.4.2.Final</version>
        </dependency>
        <dependency>
            <groupId>org.mapstruct</groupId>
            <artifactId>mapstruct-processor</artifactId>
            <version>1.4.2.Final</version>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.12</version>
        </dependency>

踩坑指南： clean install之后在生成的target文件下查看具体实现如果出现映射丢失，或者没有映射主要排查如下情况：

1、lombok一定要放在mapstruct下面

2、检查lombok版本是否过低测试时mapstuct版本为1.4.2.Final lombok版本必须为1.16.16以上的高版本

     <dependency>
            <groupId>org.mapstruct</groupId>
            <artifactId>mapstruct</artifactId>
            <version>1.4.2.Final</version>
        </dependency>
        <dependency>
            <groupId>org.mapstruct</groupId>
            <artifactId>mapstruct-processor</artifactId>
            <version>1.4.2.Final</version>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.16</version>
        </dependency>

1、干掉 BeanUtils！试试这款 Bean 自动映射工具，真心强大 2、mapstruct最佳实践 3、springboot整合mapstruct 4、SpringBoot 2.4.1整合 MapStruct 详细教程 5、MapStruct文档（九）——高级映射选项 6、MapStruct 1.3.0.Final参考指南

qingjianmoxie/beanCopy