Handle Multiple Coroutines in Kotlin

Handle Multiple Coroutines in Kotlin

In this blog, we are going to learn about how we can handle multiple coroutines in Kotlin.

When we launch coroutines in Kotlin using launch it returns a Job object as a result

Job :

We can manage that coroutine with the help of the Job object. Like it can be used to wait for the coroutine to do some work or it can be used to cancel the coroutine.

Coroutines can be controlled through the functions that are available on the Job interface. Some functions out of many that job interface offers are as follows:

• start()
• join()
• cancel()

join() function is a suspending function, It can be called from a coroutine or from within another suspending function. Job blocks all the threads until the coroutine finished its work.

cancel() method is used to cancel the coroutine, without waiting for it to finish its work. It can be said that it is just opposite to that of the join method.

Here we have created a fakeDownload function :

We launch a coroutine to get the job as a result. Which we can later use to join to wait for the operation to complete.

We can also use multiple joins for multiple coroutines to perform their task and wait for completion. For example :

Let’s clean up a little bit by using Collection<Job>.joinAll().

For example :

To learn more about Kotlin & Coroutines, you can also refer to this link -> Coroutines Guide

That’s done. I hope, this blog will be helpful to you.

Reference: https://kotlin.github.io/kotlinx.coroutines/kotlinx-coroutines-core/kotlinx.coroutines/index.html