Question

我有以下内容：

class Match{ 
    Team localTeam
    Team visitingTeam
}

class Team{
    static hasMany = [matches: Match]
}

抛出：加载插件管理器时出错：类[class myapp.Team]中的属性[matches]是一对一的双向，在反面有两个可能的属性。可以在关系[team]的另一侧命名其中一个属性，也可以使用'mappedBy'静态来定义关系映射的属性。示例：static mappedBy = [matches：'myprop']

所以，我使用'mappedBy'：

class Team{
    static hasMany = [matches: Match]
    static mappedBy = [matches: localTeam, matches: visitingTeam]
}

但是，通过这样做，当我从db获得团队时，匹配Set仅包含团队作为访问团队的匹配，这意味着它只将匹配映射到visitedTeam。

如果我编码de follow：

class Team{
    static hasMany = [matches: Match]
    static mappedBy = [matches: localTeam]
}

它只映射localTeam的匹配。

有没有办法将两个匹配（当团队是本地的，何时是访问者）映射到团队？

Answer 1

请先阅读有关GORM绩效问题的文章：https://mrpaulwoods.wordpress.com/2011/02/07/implementing-burt-beckwiths-gorm-performance-no-collections

这可能就是你要找的东西：

class Team {
   String name
   String description

   static constraints = {
    name blank: false, nullable: false
    description blank: true, nullable: true
   }

   static mapping = {
      description type: 'text'
   }

   Set<Match> getHomeMatches() {
    Match.findAllByHomeTeam(this).collect { it.homeTeam } as Set
   }

   Set<Match> getMatches() {
    Match.findAllByTeam(this).collect { it.team } as Set
   }
}


class Match {

   Team homeTeam
   Team team

   static constraints = {
    homeTeam nullable: false
    team nullable: false
   }

   static mapping = {
    id composite: ['homeTeam', 'team']
   }   
}

Answer 2

试试这个

class Team {
    static hasMany = [localTeamMatches: Match, visitingMatches: Match]
    static mappedBy = [localTeamMatches: "localTeam", visitingMatches: "visitingTeam"]
}

GORM使用hasMany映射同一Class的两个属性

2 个答案: