Sync version of async method
Solution 1:
Have a look at CountDownLatch. You can emulate the desired synchronous behaviour with something like this:
private CountDownLatch doneSignal = new CountDownLatch(1);
void main() throws InterruptedException{
asyncDoSomething();
//wait until doneSignal.countDown() is called
doneSignal.await();
}
void onFinishDoSomething(){
//do something ...
//then signal the end of work
doneSignal.countDown();
}
You can also achieve the same behaviour using CyclicBarrier
with 2 parties like this:
private CyclicBarrier barrier = new CyclicBarrier(2);
void main() throws InterruptedException{
asyncDoSomething();
//wait until other party calls barrier.await()
barrier.await();
}
void onFinishDoSomething() throws InterruptedException{
//do something ...
//then signal the end of work
barrier.await();
}
If you have control over the source-code of asyncDoSomething()
I would, however, recommend redesigning it to return a Future<Void>
object instead. By doing this you could easily switch between asynchronous/synchronous behaviour when needed like this:
void asynchronousMain(){
asyncDoSomethig(); //ignore the return result
}
void synchronousMain() throws Exception{
Future<Void> f = asyncDoSomething();
//wait synchronously for result
f.get();
}