字段类型之关系描述的特殊场景(常量关联)

场景概述

【字段类型之关系与引用】一文中已经描述了各种关系字段的常规写法，还有一些特殊场景如：关系映射中存在常量，或者M2M中间表是大于两个字段构成。

场景描述

1、PetTalent模型增加talentType字段
2、PetItem与PetTalent的多对多关系增加talentType（达人类型），
3、PetItemRelPetTalent中间表维护petItemId、petTalentId以及talentType，PetDogItem和PetCatItem分别重写petTalents字段，关系中增加常量描述。示意图如下：

实际操作步骤

Step1 新增 TalentTypeEnum

package pro.shushi.pamirs.demo.api.enumeration;

import pro.shushi.pamirs.meta.annotation.Dict;
import pro.shushi.pamirs.meta.common.enmu.BaseEnum;

@Dict(dictionary = TalentTypeEnum.DICTIONARY,displayName = "达人类型")
public class TalentTypeEnum extends BaseEnum<TalentTypeEnum,Integer> {

    public static final String DICTIONARY ="demo.TalentTypeEnum";

    public final static TalentTypeEnum DOG =create("DOG",1,"狗达人","狗达人");
    public final static TalentTypeEnum CAT =create("CAT",2,"猫达人","猫达人");
}

Step2 PetTalent模型增加talentType字段

package pro.shushi.pamirs.demo.api.model;

import pro.shushi.pamirs.demo.api.enumeration.TalentTypeEnum;
import pro.shushi.pamirs.meta.annotation.Field;
import pro.shushi.pamirs.meta.annotation.Model;

@Model.model(PetTalent.MODEL_MODEL)
@Model(displayName = "宠物达人",summary="宠物达人",labelFields ={"name"})
public class PetTalent extends AbstractDemoIdModel{
    public static final String MODEL_MODEL="demo.PetTalent";

    @Field(displayName = "达人")
    private String name;

    @Field(displayName = "达人类型")
    private TalentTypeEnum talentType;
}

Step3 修改PetItem的petTalents字段，在关系描述中增加talentType（达人类型）

    @Field.many2many(relationFields = {"petItemId"},referenceFields = {"petTalentId","talentType"},through = PetItemRelPetTalent.MODEL_MODEL )
    @Field.Relation(relationFields = {"id"}, referenceFields = {"id","talentType"})
    @Field(displayName = "推荐达人",summary = "推荐该商品的达人们")
    private List<PetTalent> petTalents;

Step4 PetDogItem增加petTalents字段，重写父类PetItem的关系描述

1. talentType配置为常量，填入枚举的值
2. 增加domain描述用户页面选择的时候自动过滤出特定类型的达人，RSQL用枚举的name

   @Field(displayName = "推荐达人")
   @Field.many2many(
           through = "PetItemRelPetTalent",
           relationFields = {"petItemId"},
           referenceFields = {"petTalentId","talentType"}
   )
   @Field.Relation(relationFields = {"id"}, referenceFields = {"id", "#1#"}, domain = " talentType == DOG")
   private List<PetTalent> petTalents;

Step5 PetCatItem增加petTalents字段，重写父类PetItem的关系描述

1. talentType配置为常量，填入枚举的值
2. 增加domain描述用户页面选择的时候自动过滤出特定类型的达人，RSQL用枚举的name

   @Field(displayName = "推荐达人")
   @Field.many2many(
           through = "PetItemRelPetTalent",
           relationFields = {"petItemId"},
           referenceFields = {"petTalentId","talentType"}
   )
   @Field.Relation(relationFields = {"id"}, referenceFields = {"id", "#2#"}, domain = " talentType == CAT")
   private List<PetTalent> petTalents;

Step6 PetCatItem增加petTalents字段，many2one关系示例

1. talentType配置为常量，填入枚举的值

2. 增加domain描述用户页面选择的时候自动过滤出特定类型的达人，RSQL用枚举的name

   @Model.model(PetPet.MODEL_MODEL)
   @Model(displayName = "宠物宠物", summary = "宠物宠物")
   public class PetPet extends IdModel {
   
   public static final String MODEL_MODEL = "demo.PetPet";
   
   @Field.many2one
   @Field(displayName = "品种")
   @Field.Relation(relationFields = {"typeId", "#CAT#"}, referenceFields = {"id", "kind"}, domain = "kind=='CAT'")
   private PetType type;
   
   @Field(displayName = "品种ID", invisible = true)
   private Long typeId;
   
   @Field(displayName = "原产地")
   private String provenance;