Mapstruct kotlin 和 @Named 注解

Mapstruct kotlin and @Named annotation

我正在将一些宠物项目从 java 转换为 kotlin,但遇到了一些无法解决的问题。在 java 中,所有编译都很好,但在转换为 Kotlin 后不需要....

...
import org.mapstruct.Mapper
import org.mapstruct.Mapping
import org.mapstruct.Named
...

@Mapper(unmappedTargetPolicy = ReportingPolicy.ERROR)
interface EffectMapper {

    @Mapping(source = "icon", target = "icon", qualifiedByName = ["convertIcon"])
    fun toDS(effectDTO: EffectDTO): EffectDS

    fun toDSarr(effectDTOArrayList: ArrayList<EffectDTO>): ArrayList<EffectDS>

    @Named("convertIcon")
    fun convertIcon(obj: String?): ByteArray? {
        return if (obj != null) {
            Base64.decode(obj, Base64.DEFAULT)
        } else {
            null
        }
    }

    companion object {
        val MAPPER = Mappers.getMapper(EffectMapper::class.java)
    }
}

Gradlereturn错误

 error: Can't generate mapping method from non-iterable type to iterable type.
    public abstract byte[] convertIcon(@org.jetbrains.annotations.Nullable()

Can't map property "java.lang.String icon" to "byte[] icon". Consider to declare/implement a mapping method: "byte[] map(java.lang.String value)".
    @org.mapstruct.Mapping(source = "icon", target = "icon", qualifiedByName = {"convertIcon"})

Can't map property "java.lang.String effect" to "one.codium.funart.DataStructure.effect.Effect effect". Consider to declare/implement a mapping method: "one.codium.funart.DataStructure.effect.Effect map(java.lang.String value)".
    public abstract one.codium.funart.DataStructure.EffectDS toDS(@org.jetbrains.annotations.NotNull()

最后就这样搞定了

@Mapper(unmappedTargetPolicy = ReportingPolicy.ERROR, uses = [EffectMapperImpl::class])
interface EffectMapper {

    fun toDS(effectDTO: EffectDTO): EffectDS

    fun toDSarr(effectDTOArrayList: ArrayList<EffectDTO>): ArrayList<EffectDS>

    companion object {
        val MAPPER: EffectMapper = Mappers.getMapper(EffectMapper::class.java)
    }
}

object EffectMapperImpl {

    fun convertIcon(obj: String?): ByteArray? {
        return if (obj != null) {
            Base64.decode(obj, Base64.DEFAULT)
        } else {
            null
        }
    }

    fun toEffect(s: String): Effect {
        return Effect(s)
    }
}

谢谢@Filip

您看到的问题是由于 convertIcon 方法未被识别为 EffectMapper 接口中的默认方法。

即使您使用 @JvmDefault,由于 KT-25960 也无法使用。我建议您将 convertIcon 方法提取到另一个 class 中的 public 静态方法中,然后通过 Mapper#uses

使用它

我使用的是 Kotlin 1.3.71-release-431,它与@JvamDefault 一起工作正常,所以你只需要在 (java).[=11= 中将你的转换方法 (toEffect) 设为静态]

Mapping(source = "sourceFiledName", target = "destinationFiledName", qualifiedByName = ["converterMethod"])
interface EffectMapper {
  fun toDS(effectDTO: EffectDTO): EffectDS
  
  fun toDSarr(effectDTOArrayList: ArrayList<EffectDTO>): ArrayList<EffectDS>
  
  companion object {
     @JvmStatic
     @Named("converterMethod")
     fun toEffect(s: String): Effect {
        return Effect(s)
      }
  }
}