MapStruct集成及使用

集成方式

1. pom.xml 中修改 maven打包plugin 配置，增加annotationProcessorPaths部分，主要是为了兼容 lombok

  	  <plugin>
  	          <groupId>org.apache.maven.plugins</groupId>
  	          <artifactId>maven-compiler-plugin</artifactId>
  	          <configuration>
  	            <source>${maven.compiler.source}</source>
  	            <target>${maven.compiler.target}</target>
  	            <annotationProcessorPaths>
  	              <path>
  	                <groupId>org.projectlombok</groupId>
  	                <artifactId>lombok</artifactId>
  	                <version>${lombok.version}</version>
  	              </path>
  	              <path>
  	                <groupId>org.mapstruct</groupId>
  	                <artifactId>mapstruct-processor</artifactId>
  	                <version>${mapstruct.version}</version>
  	              </path>
  	            </annotationProcessorPaths>
  	          </configuration>
  	        </plugin>

2. 引入 MapStructjar

            <dependency>
            <groupId>org.mapstruct</groupId>
            <artifactId>mapstruct</artifactId>
            <version>${mapstruct.version}</version>
            </dependency>

使用方式

1. 定义基类

		  public interface BaseMapStruct<D, E> {
		      /**
		       * DTO转Entity
		       *
		       * @param dto
		       * @return
		       */
		      E toEntity(D dto);
		  
		      /**
		       * Entity转DTO
		       *
		       * @param entity
		       * @return
		       */
		      @Named(value = "useMe")
		      D toDto(E entity);
		  
		      /**
		       * DTO集合转Entity集合
		       *
		       * @param dtoList
		       * @return
		       */
		      List<E> toEntity(List<D> dtoList);
		  
		      /**
		       * Entity集合转DTO集合
		       *
		       * @param entityList
		       * @return
		       */
		      @IterableMapping(qualifiedByName = "useMe")
		      List<D> toDto(List<E> entityList);
		  }

2. 创建具体映射对象，及一些关联对象

		  @Mapper
		  public interface OrderMapper extends BaseMapStruct<ItemDTO, Item> {
		      OrderMapper INSTANCE = Mappers.getMapper(OrderMapper.class);
		  
		      @Mappings({
		              @Mapping(source = "birthday", target = "birth"),
		              @Mapping(source = "birthday", target = "birthDateFormat", dateFormat = "yyyy-MM-dd HH:mm:ss"),
		              @Mapping(target = "birthExpressionFormat", expression = "java(org.apache.commons.lang3.time.DateFormatUtils.format(person.getBirthday(),\"yyyy-MM-dd HH:mm:ss\"))"),
		              @Mapping(target = "birthValue", expression = "java(person.getBirthday().getTime())"),
		              @Mapping(target = "id", ignore = true) // 忽略id，不进行映射
		      })
		      ItemDTO domain(Item person);
		  }
		  
		  @Data
		  @Accessors(chain = true)
		  public class Item {
		      private String itemName;
		      private Long price;
		      private Date birthday;
		      private Integer id;
		  }
		  
		  @Data
		  @Accessors(chain = true)
		  public class ItemDTO {
		      private String itemName;
		      private Long price;
		      private String birthDateFormat;
		      private Date birth;
		      private String birthExpressionFormat;
		      private Long birthValue;
		      private Integer id;
		  }

3. 使用

		  @Slf4j
		  public class MapStructTest {
		      @Test
		      public void test() {
		          var i = OrderMapper.INSTANCE.domain(new Item().setItemName("test")
		                  .setId(111)
		                  .setBirthday(new Date())
		                  .setPrice(111L));
		          System.out.println(JsonUtils.toJSONString(i));
		          var d = OrderMapper.INSTANCE.toEntity(i);
		  
		          System.out.println(JsonUtils.toJSONString(d));
		      }
		  }