Mapstruct-为mapping属性找到不明确的映射方法

Question

我正在使用mapstruct从一个DTO映射到另一个DTO。我有多个默认方法，但其中两个返回值为String，并且使用了与输入参数相同的类，这给了我“使用java MapStruct的mapping methods不明确”的错误。我在这里添加代码的相关部分：

@Mappings({
     @Mapping(source = "programInstance", target = "title", qualifiedByName = "title"),
     @Mapping(source = "programInstance", target = "seriesName", qualifiedByName = "seriesName"),
     @Mapping(source = "programInstance", target = "season", qualifiedByName = "season"),
     @Mapping(source = "programInstance", target = "epNumber", qualifiedByName = "epNumber"),
 })
 DTO1 mapDTOs (DTO2 dto2);

  @Named("title")
default String mapTitle(Program programInstance) {
    Optional<String> title = Utils.getObject(() -> programInstance.getTitle().getDescriptions().get(0).getValue());
    if (title.isPresent())
        return title.get();
    return null;
}
@Named("seriesName")
default String mapSeriesName(Program programInstance) {
    Optional<String> seriesName = Utils.getObject(() -> programInstance.get(0).getProgram().getTitle().getDescriptions().get(0).getValue());
    if (seriesName.isPresent())
        return seriesName.get();
    return null;
}
 @Named("season")
default Integer mapSeasonNumber(Program programInstance) {
    Optional<Integer> season = Utils.getObject(() -> programInstance.get(0).getSeasonOf().get(0).getOrderNo());
    if (season.isPresent())
        return season.get();
    return null;
}

@Named("epNumber")
default Integer mapEpNumber(Program programInstance) {
    Optional<Integer> epNumber = Utils.getObject(() -> programInstance.getEpOf().get(0).getOrderNo());
    if (epNumber.isPresent())
        return epNumber.get();
    return null;
}

错误是

发现将属性“Program ProgramInstance”映射到java.lang.String的映射方法不明确：java.lang.String mapTitle()、java.lang.String mapSeriesName（）。

Answer 1

我查了你的例子..问题是，您试图目标的字段是String类型的。

所以：

public class IvpVodOfferStatusDTO {

    private String seasonNumber;
    private String episodeNumber;
} 

MapStruct尝试将其与您提供的签名匹配：

 @Named("season")
default Integer mapSeasonNumber(Program programInstance) {
    Optional<Integer> season = Utils.getObject(() -> programInstance.get(0).getSeasonOf().get(0).getOrderNo());
    if (season.isPresent())
        return season.get();
    return null;
}

@Named("epNumber")
default Integer mapEpNumber(Program programInstance) {
    Optional<Integer> epNumber = Utils.getObject(() -> programInstance.getEpOf().get(0).getOrderNo());
    if (epNumber.isPresent())
        return epNumber.get();
    return null;
}

null

public class IvpVodOfferStatusDTO {

    private Integer seasonNumber;
    private Integer episodeNumber;
}