Managing threads in Grails Services

Question

So I have a service set up to import a large amount of data from a file the user uploads. I want to the user to be able to continue working on the site while the file is being p

Answer 1

Another way to do this is to use Spring's @Async annotation.

Add the following to resources.groovy:

beans = {
    xmlns task:"http://www.springframework.org/schema/task"
    task.'annotation-driven'('proxy-target-class':true, 'mode':'proxy')
}

Any service method you now annotate with @Async will run asynchronously, e.g.

@Async
def reallyLongRunningProcess() {
    //do some stuff that takes ages
}

If you only want one thread to run the import at a time, you could do something like this -

class MyService {
    boolean longProcessRunning = false

    @Async
    def reallyLongRunningProcess() {
        if (longProcessRunning) return

        try {
            longProcessRunning = true
            //do some stuff that takes ages
        } finally {
            longProcessRunning = false
        }
    }
}