mapsturct各种情况使用

1、常用注解

@Mapper(componentModel = "spring",nullValuePropertyMappingStrategy = NullValuePropertyMappingStrategy.IGNORE),builder = @Builder(disableBuilder = true)

参数	作用
componentModel	componentModel="spring"必加将这个实现类Spring 容器来管理，不然需要手动实现否则报错 A component required a bean of type 'com.xxx.xxx' that could not be found
nullValuePropertyMappingStrategy	定空值属性映射策略这里 NullValuePropertyMappingStrategy.IGNORE 表示直接忽略不转换
builder = @Builder(disableBuilder = true)	注解用于禁用构建器方法的生成，确保使用传统的构造函数进行对象创建。

2、基本使用

目标实体类与源实体类参数类型参数名相同时 xxx<实体类> 或者直接实体类都可以

@Mapper(componentModel = "spring",nullValuePropertyMappingStrategy = NullValuePropertyMappingStrategy.IGNORE)

public interface UserConvert {
   
    /**
     * user inToOut
     * NullValuePropertyMappingStrategy.IGNORE 当参数未null时候不转换
     * @param userInput
     * @return
     */
    UserOutput userConvert(UserInput userInput);
}

3、目标与源实体类属性名不一致

问题	解决方法
实体类	直接使用 @Mapping注解target为目标参数名（左） source为源参数名（右）
xxx<实体类>	先写xxx<实体类> convert（xxx<实体类> xxx) 然后再将写一个转换出参为目标转换中泛型入参为源目标泛型之后将注解加载这里之后就跟↑一样。


    List<AggOutRepairOrderLabourTwoBO> labourAggOutBoToAggOutBo(List<RepairOrderLabourSumAggOutBO> list);

    @Mapping(target = "repairName",source = "srvName")
    @Mapping(target = "jobName",source = "srvTypeName")
    @Mapping(target = "workshopTeam",source = "workByName")
    AggOutRepairOrderLabourTwoBO labourAggOutBoToAggOutBo(RepairOrderLabourSumAggOutBO list);

4、复杂转换情况

1、多个入参属性名与出参属性名不一致

参数expression在MapStruct中用于指定一个Java表达式的字符串。这个表达式可以在生成映射代码时被用来生成目标属性的值。

@Data
@AllArgsConstructor
@NoArgsConstructor
public class ComprehensiveInputVO {
    private MusicDTO music1;
    private List<UserInput> userInputList1;
}

@Data
@AllArgsConstructor
@NoArgsConstructor
public class ComprehensiveOutputVO {
    private MusicDTO music2;
    private List<UserInput> userInputList2;
}

  @Mapping(target = "music2", source = "music1")
  @Mapping(target = "userInputList2", source = "userInputList1")
  ComprehensiveOutputVO complexConvert(ComprehensiveInputVO comprehensiveInputVO);

2、多个入参属性名与出参属性名不一致，同时入参属性中的属性也不一致

首先如果是普通实体类 - 直接对应名字.属性目标属性和源属性即可

    @Mapping(target = "music2.musicName",source = "music1.userMusicName")
    @Mapping(target = "music2.ranking",source = "music1.rank")
    @Mapping(target = "music2.mySinger",source = "music1.singer")
    @Mapping(target = "music2.mYLyricist",source = "music1.lyricist")
    @Mapping(target = "userInputList2",source = "userInputList1")
    ComprehensiveOutputVO complexConvert(ComprehensiveInputVO comprehensiveInputVO);

若还有其他复杂，如list<实体类> 这种不仅名字不一样，属性也有不一样，先使用 @Mapping(target = "userInputList2",source = "userInputList1") 让他能找到对应属性，然后比如是list 再按照3的程序走一遍即可

 @Mapping(target = "password",source = "userPassword")
    @Mapping(target = "name",source = "userName")
    UserOutput userConvert(UserInput userInput);

    /**
     * userConvertList
     * @param inputList
     * @return
     */
    List<UserOutput> userConvertList(List<UserInput> inputList);


/*
* @Mapping(expression = "java(musicDTO1.getMusicName() + "10086")",target = "music1.musicName")
    ComprehensiveOutputVO complexConvert(ComprehensiveInputVO comprehensiveInputVO); 这样给属性赋值也行
*/

5、其他情况

处理逻辑，调用静态方法，自己手动写验证参数是否正确等等

 @Mapping(expression = "java(com.example.problems.bo.Constant.templatePost(musicDTO1.getMusicName()))", target = "music1.musicName")
    ComprehensiveOutputVO complexConvert(ComprehensiveInputVO comprehensiveInputVO);

public class Constant {
    private String name = "校长";

    public static String templatePost(String code) {
        if (StringUtils.isEmpty(code)) {
            return code;
        }
        switch (code) {
            case "123":
                return "SA";
            case "1234":
                return "CR";
            default:
                return "meiyou";
        }
    }
}

@Mapping(expression = "java(SuspendConvert.compareSize(bo))", target = "temp")
FactoryPageInBo toFactoryPageInBo(BffFactoryPageInBo bo);

 static Integer compareSize(BffFactoryPageInBo bo) {
    处理逻辑
    }

mapsturct 避坑指南