Coroutines, suspend functions, dispatchers, structured concurrency, channels, Flow and StateFlow.
40 cards · basic cards · AI-written, checked twice. Edit anything.
- What is a suspend function in Kotlin?
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A function that can be paused and resumed without blocking the thread, enabling non-blocking concurrent operations.- What does the suspend keyword do?
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Marks a function as suspendable, so it can call other suspend functions and be invoked only from coroutines or another suspend function.- What does the launch builder return?
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A Job object representing the launched coroutine, without blocking.- What does the async builder return?
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A Deferred object that represents a future result that can be awaited.- What does runBlocking do?
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Blocks the current thread until the coroutine completes; used mainly in tests or main functions.- What is structured concurrency?
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A paradigm where each coroutine is launched in a scope and all children must complete before the scope exits, preventing leaked coroutines.- What is a CoroutineScope?
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An interface defining the lifetime and hierarchy of coroutines within it.- What does Job represent?
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The lifecycle of a coroutine, with states like New, Active, Completing, and Completed.- What is Dispatcher.Main?
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A coroutine dispatcher that runs code on the main thread, used for UI updates.- What is Dispatcher.Default?
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A dispatcher for CPU-intensive work, using a thread pool sized to the number of CPU cores.- What is Dispatcher.IO?
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A dispatcher optimized for blocking IO operations like network or file access.- What is Dispatcher.Unconfined?
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A dispatcher that does not enforce thread affinity; generally not recommended for production.- What does withContext do?
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Switches the dispatcher for a block of code and resumes on the original dispatcher after completion.- Why is GlobalScope discouraged?
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It breaks structured concurrency because coroutines are not tied to a parent scope and can leak.- What is the difference between Job and SupervisorJob?
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SupervisorJob does not propagate child failures to the parent, while Job does.
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