Grails 2.3.7 Optimistic Locking version is updated every time a Command Object is submitted

Question

I have the following

def save(ACommand command){
  ...
}

@Validateable
class ACommand implements Serializable
{
  ADomainObject bundleDef
}

but every time save is called the version is incremented. So if I open up two browsers and submit a different value in succession, instead of getting an error the second time as I would expect, the value is updated.

I also tried using two different sessions with no difference

Update

If I use breakpoints and submit before the other one is completed it works fine. However, If I let the first complete then submit the second without a refresh the version is updated to the newer one (which I don't want) and the change goes through.

Update 2

When you perform updates Hibernate will automatically check the version property against the version column in the database and if they differ will throw a StaleObjectException. This will roll back the transaction if one is active.

per Grails this should work seems to me.

could you show the save implemenation, to see how the optimistic locking case is handled in the controller? otherwise the code snippet does not make much sense, thx :) — Mario David
I am using the auto locking in Grails not sure what you want to see? It just saves an object from a form pretty basic stuff — Jackie

Dónal Dónal · Accepted Answer · 2014-04-23T18:06:07

AFAIK, you need to check the version and handle failures yourself - it doesn't happen automatically. You can do this with code like this:

/**
 * Returns a boolean indicating whether the object is stale
 */
protected boolean isStale(persistedObj, versionParam = params.version) {

    if (versionParam) {
        def version = versionParam.toLong()
        if (persistedObj.version > version) {
            return true
        }
    } else {
        log.warn "No version param found for ${persistedObj.getClass()}"
    }
    false
}

you can call isStale from an action like this

def update() {
    Competition competition = Competition.get(params.id)

    if (isStale(competition)) {
        // handle stale object
        return
    }

    // object is not stale, so update it
}

Grails 2.3.7 Optimistic Locking version is updated every time a Command Object is submitted

2 Answers