hibernate - GORM 组合 - 具有多对一关系的嵌入式域引发 org.hibernate.MappingException

Question

我正在尝试在 Grails 2.2.1 中使用具有多对一关系的嵌入式域。这是我正在尝试做的事情的简化版本。

我正在映射到现有的数据库表:

create table incident (id bigint generated by default as identity, state_id bigint not null, primary key (id));
create table state (id bigint generated by default as identity, name varchar(255) not null, primary key (id));
alter table incident add constraint FK52F44D27499E79E foreign key (state_id) references state;

映射到“事件”表的域:

class Incident {
    Vehicle vehicle
    static embedded = ['vehicle']
}

class Vehicle{
    State state
    static mapping = {
        state column: 'state_id'
    }   
}  

映射到“状态”表的域:

class State {
    String name 
}

当我尝试运行我的应用程序时，出现以下错误:

Message: Error creating bean with name 'transactionManagerPostProcessor': Initialization of bean failed; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'transactionManager': Cannot resolve reference to bean 'sessionFactory' while setting bean property 'sessionFactory'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sessionFactory': Invocation of init method failed; nested exception is org.hibernate.MappingException: Could not determine type for: test.State, at table: incident, for columns: [org.hibernate.mapping.Column(vehicle_state)]

是否可以在嵌入式域中进行多对一关联？

-- 更新 ——

我最终使用了一种解决方法来获取状态。

class Vehicle{

    static transients = [ "state" ]

    Long stateId

    static mapping = {
        stateId column: 'state_id'  
    }

    State getState(){
        State.get(this.stateId)
    }
}

Answer 1

从 Grails 2.2.1 开始，嵌入式域类有几个可用性问题，使它们难以使用，尤其是在遗留数据库中。

关系不起作用

自定义列映射不起作用

您最好直接在所属类中映射列，然后创建一个辅助方法来处理嵌入的实体。

例如。:

// grails-app/domain/yourpkg/Incident.groovy
class Incident {
    State state

    public Vehicle getVehicleData() {
        return new Vehicle(state: state)
    }

    public void updateWithVehicle(Vehicle vehicle) {
        state = vehicle.state
    }

    static mapping = {
        state column: 'state_id'
    }
}

// src/groovy/yourpkg/Vehicle.groovy
class Vehicle {
    State state
}