Grails挂钩到GORM beforeUpdate()

Question

我对嵌套域类有内部要求,我希望将父关系的更新传播给子项.代码示例可以说清楚:

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

当父里程碑的estimatedEnd更新时,我希望孩子的估计会自动更新相同的金额.GORM的beforeUpdate()钩子似乎是一个合乎逻辑的地方:

为了让生活更轻松,我想使用一些简单的Date算法,所以我在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)
    }

我明白了:

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

我有一个解决方案给你.

1)更新milestone1的estimatedEnd后,在第二次保存调用中调用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,因为您正在比较两个稍微不同的日期(在每个Milestone构造函数中使用单独的Date对象,因此第二个日期稍晚于/大于第一个日期.)如果你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,
        )

那么断言就会成功.在比较略有不同的日期的最佳方法方面,我将留给您下一步做什么,但您可能必须容忍毫秒级的精度差异.

希望有所帮助,

约旦