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Java - Handling Non-Blocking Calls

In my application I am using a third-party API. It is a non-blocking method which returns immediately. I have a collection of elements over which I have to invoke this method.

Now, my problem is that I have to find a way till all the method execution gets completed and do my next operation. How can I handle this? I cannot modify the third-party API.

In short it looks like this

for(Object object: objects){
 methodA(object); //this is a non-blocking call and returns immediately
}
// here I want to do my next task only after all the methodA calls completed execution
Solution

  • What you are asking for is impossible ... unless the third party API also includes some method that allows you to wait until one or more calls to methodA have completed.

    Does it?

    EDIT

    As Kathy Stone notes, another possibility is that the API might have a callback mechanism, whereby a thread (behind the API) that is doing the work started by the methodA call "calls back" to your code. (There would need to be some other method in the API that allows you to register the callback object.)

    There are other possibilities as well ... (some too horrible to mention) ... but they all entail the API being designed to support synchronization with end of the tasks started by methodA.