依赖

    <properties>
        <org.mapstruct.version>1.4.1.Final</org.mapstruct.version>
        <org.projectlombok.version>1.18.12</org.projectlombok.version>
    </properties>
    <dependencies>
        <!-- mapstruct，需要对应lombok版本-->
        <dependency>
            <groupId>org.mapstruct</groupId>
            <artifactId>mapstruct-jdk8</artifactId>
            <version>${org.mapstruct.version}</version>
        </dependency>
        <dependency>
            <groupId>org.mapstruct</groupId>
            <artifactId>mapstruct-processor</artifactId>
            <version>${org.mapstruct.version}</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>org.mapstruct</groupId>
            <artifactId>mapstruct</artifactId>
            <version>${org.mapstruct.version}</version>
        </dependency>
        <!-- 升级lombok版本 -->
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>${org.projectlombok.version}</version>
            <scope>provided</scope>
        </dependency>
    </dependencies>

接口类

/**
 * @author UnityAlvin
 * @date 2021/9/28 18:57
 */
@Mapper(componentModel = "spring")
public interface BusinessCovertBasic {
    BusinessCovertBasic INSTANCE = Mappers.getMapper(BusinessCovertBasic.class);
    // 手动设置某个值：expression中，不包含的类需要具体到包名
    @Mappings({
            // LocalDateTime转Date
            @Mapping(target = "createTime",
                    expression = "java(java.util.Date.from(omsOrder.getCreateTime()" +
                            ".atZone(java.time.ZoneId.systemDefault()).toInstant()))"),
            // 时间戳转Date
            @Mapping(target = "validDate", expression = "java(new java.util.Date(omsOrder.getValidDate()))"),
            // 单位为分的金额转单位为元
            @Mapping(target = "refundFee",
                    expression = "java(new java.math.BigDecimal(omsOrder.getRefundFee())" +
                            ".divide(new java.math.BigDecimal(100), 2, java.math.BigDecimal.ROUND_HALF_UP))"),     
            // 对象/List转JSON
            @Mapping(target = "baseInfo",
                    expression = "java(com.alibaba.fastjson.JSON.toJSONString(omsOrder.getBaseInfo()))"), 
            // 直接为某个字段赋具体值
            @Mapping(target = "orderNoteChangeFlag", expression = "java(0)")
    })
    OmsOrderSimpleResponse orderToOmsOrderSimpleResponse(OmsOrder omsOrder);
    // 将原有source列的值转换到target列上
    @Mappings({
            @Mapping(source="id", target="mchId")
    })    
    OmsOrderItemView orderItemToOrderItemView(OmsOrderItem orderItem);
    // 忽略某个字段的映射 
    // 方式2：注解
    // https://blog.csdn.net/zyw61483/article/details/112990760
    @Mappings({
            @Mapping(target="mchId", ignore=true)
    })    
    OmsOrderItemView orderItemToOrderItemView(OmsOrderItem orderItem);
}