hibernate - Grails钩入GORM beforeUpdate()

Question

我对嵌套域类有一个内部要求，我想将对父级关系的更新传播到子级。一个代码示例可以清楚地表明:

class Milestone {
    static belongsTo = [project:Project]
    static hasMany = [goals:OrgGoals, children:Milestone]
    String name
    Date start
    Date estimatedEnd
    Date achievedEnd
    ...
}

当父级里程碑的estimateEnd更新时，我希望 child 的估算值自动更新相同的数量。 GORM's beforeUpdate() hook似乎很适合这样做:

为了使生活更轻松，我想使用一些 simple Date arithmetic，因此我在Milestone类中添加了以下方法:

def beforeUpdate()
    {
        // check if an actual change has been made and the estimated end has been changed
        if(this.isDirty() && this.getDirtyPropertyNames().contains("estimatedEnd"))
        {
            updateChildEstimates(this.estimatedEnd,this.getPersistentValue("estimatedEnd"))
        }
    }

private void updateChildEstimates(Date newEstimate, Date original)
    {
        def difference = newEstimate - original
        if(difference > 0)
        {
            children.each{ it.estimatedEnd+= difference }
        }
    }

没有编译错误。但是，当我运行以下集成测试时:

void testCascadingUpdate() {
        def milestone1 = new Milestone(name:'test Parent milestone',
            estimatedEnd: new Date()+ 10,
        )
        def milestone2 = new Milestone(name:'test child milestone',
            estimatedEnd: new Date()+ 20,
        )
        milestone1.addToChildren(milestone2)
        milestone1.save()
        milestone1.estimatedEnd += 10
        milestone1.save()
        assert milestone1.estimatedEnd != milestone2.estimatedEnd
        assert milestone2.estimatedEnd == (milestone1.estimatedEnd + 10)
    }

我得到:

Unit Test Results.

    Designed for use with JUnit and Ant.
All Failures
Class   Name    Status  Type    Time(s)
MilestoneIntegrationTests   testCascadingUpdate Failure Assertion failed: assert milestone2.estimatedEnd == (milestone1.estimatedEnd + 10) | | | | | | | | | | | Mon Jun 06 22:11:19 MST 2011 | | | | Fri May 27 22:11:19 MST 2011 | | | test Parent milestone | | false | Fri May 27 22:11:19 MST 2011 test child milestone

junit.framework.AssertionFailedError: Assertion failed: 

assert milestone2.estimatedEnd == (milestone1.estimatedEnd + 10)
       |          |            |   |          |            |

       |          |            |   |          |            Mon Jun 06 22:11:19 MST 2011
       |          |            |   |          Fri May 27 22:11:19 MST 2011
       |          |            |   test Parent milestone

       |          |            false
       |          Fri May 27 22:11:19 MST 2011
       test child milestone

    at testCascadingUpdate(MilestoneIntegrationTests.groovy:43)

    0.295

这表明beforeUpdate没有触发并执行我想要的操作。有任何想法吗？

Answer 1

我为您提供解决方案。

1)更新里程碑1的EstimatedEnd之后，在第二个保存调用中调用save(flush:true)。这将强制beforeUpdate()立即触发。

2)即使在执行＃1之后，您的断言仍将继续失败，因为您正在比较2个稍有不同的日期(您在每个Milestone构造函数中使用单独的Date对象，因此第二个日期比第一个日期稍晚/更大)。您使用了相同的日期实例，例如

Date date = new Date() 
def milestone1 = new Milestone(name:'test Parent milestone',
            estimatedEnd: date + 10)
def milestone2 = new Milestone(name:'test child milestone',
            estimatedEnd: date + 20,
        )

那么断言将成功。我将根据最佳方式比较稍有不同的日期留给您下一步要做什么，但是您可能必须忍受毫秒级的精度差异。

希望能有所帮助，

约旦