如果更改了根对象中的简单属性，JaVers 会检测子对象的更改

Question

我使用 Kotlin，我正在尝试将两个复杂对象（具有多个循环）与 JaVers 进行比较。这些对象使用多个 Id-Properties。因此，我创建了 Id-类以便每个 class 都有一个 Id-属性。在 Id-类中，我还使用了对根对象的引用，因为我需要使用它们来为我的数据库创建主键。

当我将两个对象与根对象中的单个更改进行比较时，JaVers 应该只列出一个 ValueChange。但是 JaVers 却发现了 5 个更改（NewObject-child、ObjectRemoved-child、ReferenceChanged-child、ListChange-root、ValueChanged-root）。为了解决这个问题，我更新了子对象的 equals 和 hashCode 方法，以在计算相等性时检查根对象的 id 而不是根对象本身 ==> root1.childList == root2.childList returns true. 有什么想法可以教 JaVers 没有子对象发生变化吗？

League.kt - 根对象

@Entity
data class League(@EmbeddedId val leagueId: LeagueId? = null,
                  var name: String? = null,
                  var region: String? = null,
                  @OneToMany(cascade = [CascadeType.ALL], orphanRemoval = true)
                  var groups: List<TeamGroup>? = null,
                  @OneToMany(cascade = [CascadeType.ALL], orphanRemoval = true)
                  var matchDays: List<MatchDay>? = null) : Serializable {

    override fun equals(other: Any?): Boolean {
        if (this === other) return true
        if (javaClass != other?.javaClass) return false

        other as League

        if (leagueId != other.leagueId) return false
        if (name != other.name) return false
        if (region != other.region) return false
        if (groups?.map { it.teamGroupId }?.toSet() != other.groups?.map { it.teamGroupId }?.toSet()) return false
        if (matchDays?.map { it.matchDayId }?.toSet() != other.matchDays?.map { it.matchDayId }?.toSet()) return false

        return true
    }

    override fun hashCode(): Int {
        var result = leagueId?.hashCode() ?: 0
        result = 31 * result + (name?.hashCode() ?: 0)
        result = 31 * result + (region?.hashCode() ?: 0)
        result = 31 * result + (groups?.map { it.teamGroupId }?.toSet()?.hashCode() ?: 0)
        result = 31 * result + (matchDays?.map { it.matchDayId }?.toSet()?.hashCode() ?: 0)
        return result
    }
}

LeagueId.kt - 根对象 ID

data class LeagueId(val season : String? = null, val abb : String? = null) : Serializable {

    override fun equals(other: Any?): Boolean {
        if (this === other) return true
        if (javaClass != other?.javaClass) return false

        other as LeagueId

        if (season != other.season) return false
        if (abb != other.abb) return false

        return true
    }

    override fun hashCode(): Int {
        var result = season?.hashCode() ?: 0
        result = 31 * result + (abb?.hashCode() ?: 0)
        return result
    }
}

TeamGroup.kt - 子对象

@Entity
data class TeamGroup(@EmbeddedId val teamGroupId: TeamGroupId? = null,
                     val name: String? = null,
                     val mode: String? = null,
                     val tableMode: Int? = null,
                     @OneToMany(mappedBy = "group", cascade = [CascadeType.ALL], orphanRemoval = true)
                     var teams: List<Team>? = null,
                     @OneToMany(mappedBy = "group", cascade = [CascadeType.ALL], orphanRemoval = true)
                     var matches: List<Match>? = null,
                     var remarks: String? = null,
                     @OneToMany(cascade = [CascadeType.ALL], orphanRemoval = true)
                     var rows: List<Row>? = null) : Serializable {

    override fun toString(): String {
        return "TeamGroup(id=${teamGroupId?.id}, nr=${teamGroupId?.nr}, name=$name, mode=$mode, " +
                "tableMode=$tableMode, teams=$teams, matches=$matches, remarks=$remarks, rows=$rows, " +
                "league=${teamGroupId?.league?.leagueId?.season}-${teamGroupId?.league?.leagueId?.abb})"
    }

    override fun equals(other: Any?): Boolean {
        if (this === other) return true
        if (javaClass != other?.javaClass) return false

        other as TeamGroup

        if (teamGroupId != other.teamGroupId) return false
        if (name != other.name) return false
        if (mode != other.mode) return false
        if (tableMode != other.tableMode) return false
        if (teams?.map{it.id}?.toSet() != other.teams?.map{it.id}?.toSet()) return false
        if (matches?.map{it.matchId}?.toSet() != other.matches?.map{it.matchId}?.toSet()) return false
        if (remarks != other.remarks) return false
        if (rows?.map{it.rowId}?.toSet() != other.rows?.map{it.rowId}?.toSet()) return false

        return true
    }

    override fun hashCode(): Int {
        var result = teamGroupId?.hashCode() ?: 0
        result = 31 * result + (name?.hashCode() ?: 0)
        result = 31 * result + (mode?.hashCode() ?: 0)
        result = 31 * result + (tableMode ?: 0)
        result = 31 * result + (teams?.map{it.id}?.toSet()?.hashCode() ?: 0)
        result = 31 * result + (matches?.map{it.matchId}?.toSet()?.hashCode() ?: 0)
        result = 31 * result + (remarks?.hashCode() ?: 0)
        result = 31 * result + (rows?.map{it.rowId}?.toSet()?.hashCode() ?: 0)
        return result
    }
}

TeamGroupId.kt - 子对象 ID

data class TeamGroupId(@ManyToOne val league: League? = null, val id : Int? = null, val nr : Int? = null) : Serializable {

    override fun equals(other: Any?): Boolean {
        if (this === other) return true
        if (javaClass != other?.javaClass) return false

        other as TeamGroupId

        if (league?.leagueId != other.league?.leagueId) return false
        if (id != other.id) return false
        if (nr != other.nr) return false

        return true
    }

    override fun hashCode(): Int {
        var result = league?.leagueId?.hashCode() ?: 0
        result = 31 * result + (id ?: 0)
        result = 31 * result + (nr ?: 0)
        return result
    }
}

更新

问题是在子对象的 ID 中引用了根对象。如果我从 id 中删除此引用并移动到对象本身，则 JaVers 只会检测到一个更改。由于我的数据模型，我不确定是否可以在每个 id 对象中删除此引用。 @DiffIgnore 在 Id-属性中不起作用，因为它被作为 ValueObject 处理。

Answer 1

问题是由您的实体的 InstanceId 值错误引起的。由于您有复杂的对象作为实体 ID，因此 JaVers 使用 reflectiveToString() 函数来创建 ID 的字符串表示形式。在您的情况下，它会产生非常糟糕的结果，因为您有循环（ID 具有对拥有实体的引用）。

幸运的是，您可以使用 JaversBuider.registerValueWithCustomToString() 注册自定义 toString() 函数，例如：

@TypeName("Entity")
class Entity {
    @Id Point id
    String data
}

class Point {
    double x
    double y

    String myToString() {
        "("+ (int)x +"," +(int)y + ")"
    }
}

def "should use custom toString function for complex Id"(){
  given:
  Entity entity = new Entity(id: new Point(x: 1/3, y: 4/3))

  when: "default reflectiveToString function"
  def javers = JaversBuilder.javers()
          .build()
  GlobalId id = javers.getTypeMapping(Entity).createIdFromInstance(entity)

  then:
  id.value() == "Entity/0.3333333333,1.3333333333"

  when: "custom toString function"
  javers = JaversBuilder.javers()
          .registerValueWithCustomToString(Point, {it.myToString()})
          .build()
  id = javers.getTypeMapping(Entity).createIdFromInstance(entity)

  then:
  id.value() == "Entity/(0,1)"
}

另请参阅有关实体 ID 的更新文档 https://javers.org/documentation/domain-configuration/#entity-id

如果更改了根对象中的简单属性，JaVers 会检测子对象的更改

JaVers detects changes in childs if simple property in root object is changed

java

kotlin

javers

更新

如果更改了根对象中的简单 属性，JaVers 会检测子对象的更改

JaVers detects changes in childs if simple property in root object is changed

java

kotlin

javers

更新

如果更改了根对象中的简单属性，JaVers 会检测子对象的更改