Apache Avro GenericRecords with MapStruct example

CatalogItemEntity.java

package petstore.catalog.elasticsearch;

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

import org.apache.avro.generic.GenericRecord;
import org.mapstruct.Mapper;
import org.mapstruct.Mapping;
import org.mapstruct.Qualifier;
import org.springframework.data.annotation.Id;
import org.springframework.data.elasticsearch.annotations.Document;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.Getter;

/**
 * @author fabiojose
 */
@Data
@Document(indexName = "catalogs", type = "item")
public class CatalogItemEntity {

    @Id
    private String id;
    
    private String catalogId;
    private String productId;
    private String productName;
    private String productDescription;
    private Double price;
    private String imageUrl;

    @Mapper(
        componentModel = "spring" 
    )
    public interface EntityMapper {

        @Mapping(target = "id",
            expression = "java(java.util.UUID.randomUUID().toString())")
        @Mapping(
            source = "item",
            target = "catalogId",
            qualifiedBy = CatalogId.class)
        @Mapping(source = "item",
            target = "productId",
            qualifiedBy = ProductId.class)
        @Mapping(source = "item",
            target = "productName",
            qualifiedBy = ProductName.class)
        @Mapping(source = "item",
            target = "productDescription",
            qualifiedBy = ProductDescription.class)
        @Mapping(source = "item",
            target = "price",
            qualifiedBy = Price.class)
        @Mapping(source = "item",
            target = "imageUrl",
            qualifiedBy = ImageUrl.class)
        CatalogItemEntity map(Wrapper avro);

        /**
         * To wrapper the {@link GenericRecord}
         */
        @Getter
        @AllArgsConstructor
        public static class Wrapper {
            private GenericRecord item;
        }

        default Object getObject(String key, GenericRecord g) {
            GenericRecord data = (GenericRecord)g.get("data");

            if(null == data) {
                return null;
            }

            return data.get(key);
        }

        default String getString(String key, GenericRecord g){
            GenericRecord data = (GenericRecord)g.get("data");

            if(null== data){
                return null;
            }

            CharSequence cs = (CharSequence)data.get(key);
            
            return cs.toString();
        }

        @CatalogId
        default String catalogId(GenericRecord g){
            return getString("catalogId", g);
        }

        @ProductId
        default String productIdOf(GenericRecord g) {
            return getString("productId", g);
        }

        @ProductName
        default String productNameOf(GenericRecord g){
            return getString("productName", g);
        }

        @ProductDescription
        default String productDecriptionOf(GenericRecord g){
            return getString("productDescription", g);
        }

        @Price
        default Double price(GenericRecord g) {

            Object priceObj = getObject("price", g);
            if(null == priceObj) {
                return null;
            }

            return (Double)priceObj;
        }

        @ImageUrl
        default String imageUrlOf(GenericRecord r) {
            return getString("image", r);
        }

        @Qualifier
        @Target({ElementType.ANNOTATION_TYPE, ElementType.METHOD})
        @Retention(RetentionPolicy.SOURCE)
        public @interface CatalogId {}
        
        @Qualifier
        @Target(ElementType.METHOD)
        @Retention(RetentionPolicy.SOURCE)
        @interface ProductId {}

        @Qualifier
        @Target(ElementType.METHOD)
        @Retention(RetentionPolicy.SOURCE)
        @interface ProductName {}    

        @Qualifier
        @Target(ElementType.METHOD)
        @Retention(RetentionPolicy.SOURCE)
        @interface ProductDescription {}

        @Qualifier
        @Target(ElementType.METHOD)
        @Retention(RetentionPolicy.SOURCE)
        public static @interface Price {}

        @Qualifier
        @Target(ElementType.METHOD)
        @Retention(RetentionPolicy.SOURCE)
        @interface ImageUrl {}
    }

}