Question

I have a requirement to start a task..Now many threads can start this task and this task normally takes 4-5 seconds to complete. I want to prevent the starting of a task if this task has been already started by some other thread.
In order to implement this requirement, I am thinking of starting a timer or stopwatch in a different thread whenever the task is started by some thread. Now when the timer times out after a configured time-interval, another thread can starts a task.
So, is starting a timer or stopwatch in a different thread to see if the particular time has been reached is a good solution?Is there any good alternative for it?

Answer 1

If you are trying to do this in java then you can consider using a synchronized block on the Object Oriented approach on JAVA.

So any task that you want to make sure is done by one thread at a time then make a class and a synchronized method in that class, also make sure you all the threads share the same object of the class and call this method in which they want to perform the task.

For Example

Class SyncTask{


synchronized void task1(){

//Perform your task here


}

}

Create the object of this class once during the lifetime of your application and then use this same object across all the threads and let them call this method to which you want to perform your task.

In the case of multiple threads invoking this method at the same time. JVM will take care of the sequence and if one thread is already performing a task, the others calling it will wait for the first one to finish.

In this way you will be sure that only on thread is performing the task at any given time.

I hope this helps.