如何在criteria中使用'in'查询子对象?

How do I use 'in' in criteria to query sub-objects?

我想查询给定列表中所有具有子对象的对象。

class Parent {
    Child child

    static namedQueries = {
        getParentsByListOfChildren { childList ->
            'in'('child', childList.collect {it.id})
        }
    }
}

class Child {
}

def listOfChildren = [child1, child2]  // child1 and child2 are instances of Child
def results = Parent.getParentsByListOfChildren(listOfChildren)

我在集成测试中遇到以下异常:

property.BasicPropertyAccessor HHH000122: IllegalArgumentException in class: com.me.Parent, getter method of property: id
| Failure:  getParentsByListOfChildren correctly filters trains (com.me.ParentIntegrationSpec)
|  org.hibernate.PropertyAccessException: IllegalArgumentException occurred calling getter of com.me.parent.id
    at org.grails.datastore.gorm.GormStaticApi.withCriteria_closure11(GormStaticApi.groovy:304)
    at org.grails.datastore.mapping.core.DatastoreUtils.execute(DatastoreUtils.java:302)
    at org.grails.datastore.gorm.AbstractDatastoreApi.execute(AbstractDatastoreApi.groovy:37)
    at org.grails.datastore.gorm.GormStaticApi.withCriteria(GormStaticApi.groovy:303)

如何在对象不是简单对象的条件中使用 in?我假设我需要使用 Child?

的 ID

除了@dmahapatro 建议的一种方法,您还可以使用其他两种方法编写条件查询。我将它们指向这里以供参考。

解决方案 1:@dmahapatro 建议

getParentsByListOfChildren { childList ->
    'in'('child.id', childList*.id )
}

解决方案 2:

getParentsByListOfChildren { childList ->
    createAlias("child", "childFoo")   // Name is just an example, you can use anything in second parameter
    'in'('childFoo.id', childList*.id)
}

解决方案 3:

getParentsByListOfChildren { childList ->
    child {
        'in'('id', childList*.id)
    }
}

大同小异,只是写法不同罢了。