Question

在My Grails服务中，我希望以异步方式运行一部分方法。

以下是2.3.x http://grails.org/doc/2.3.0.M1/guide/async.html

的文档

我做

public class MyService {
    public void myMethod() {
        Promise p = task {
            // Long running task
        }
        p.onError { Throwable err ->
            println "An error occured ${err.message}"
        }
        p.onComplete { result ->
            println "Promise returned $result"
        }
        // block until result is called
        def result = p.get()
    }
}

但是，我想在没有任何阻挡的情况下执行我的。 p.get()方法阻止。如何在没有任何阻塞的情况下执行promise。我不在乎myMethod()是否返回，它是一种火与忘记的方法。

Answer 1

所以，根据documentation，如果你不打电话给.get()或.waitAll()，而只是使用onComplete，你就可以不受阻碍地运行你的任务当前的主题。

这是一个非常愚蠢的例子，我在控制台中作为概念证明。

import static grails.async.Promises.*
def p = task {
    // Long running task
    println 'Off to do something now ...'
    Thread.sleep(5000)
    println '... that took 5 seconds'
    return 'the result'
}

p.onError { Throwable err ->
    println "An error occured ${err.message}"
}
p.onComplete { result ->
    println "Promise returned $result"
}

println 'Just to show some output, and prove the task is running in the background.'

运行上面的示例会给出以下输出：

Off to do something now ...  
Just to show some output, and prove the task is running in the background.  
... that took 5 seconds   
Promise returned the result

在Grails 2.3中运行异步

1 个答案: