42 lines
1.2 KiB
Plaintext
42 lines
1.2 KiB
Plaintext
== Why is this an issue?
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Sometimes there is the need to cancel the execution of a coroutine after a given period of time. You can do this manually by combining the `delay()` and `cancel()` functions. However, this technique is verbose and error-prone. An easier way to manage timeouts is using the function `withTimeout()` or `withTimeoutOrNull()`.
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The `withTimeout` function will throw a `TimeoutCancellationException` when the timeout is reached, while `withTimeoutOrNull` will simply return `null` instead.
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This rule raises an issue if timeout mechanisms are implemented manually instead of using appropriate built-in functions.
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=== Noncompliant code example
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[source,kotlin]
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----
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suspend fun main() {
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coroutineScope {
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val job = launch {
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delay(2000L)
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println("Finished")
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}
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delay(500L)
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job.cancel()
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}
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}
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----
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=== Compliant solution
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[source,kotlin]
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----
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suspend fun main() {
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coroutineScope {
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withTimeoutOrNull(1000L){
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delay(2000L)
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println("Finished")
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}
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}
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}
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----
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== Resources
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* https://kotlinlang.org/docs/cancellation-and-timeouts.html[Cancellation and timeouts]
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