CoRoutine Highlighted

• CoRoutine is like a light weight thread, that is running in application layer (not in operating system layer).
• A coroutine can suspend on one thread and resume on a different thread
  • At any given moment, a coroutine runs on exactly one thread.
  • The dispatcher determines which thread(s) a coroutine uses.
    • Multiple coroutines can run on the same thread (one at a time though).
• By default one co-routine throwing (non CancellationException) uncaught exception will cancel job hierarchy, meaning:
  • Cancel parent (recursively). Parent is determined through job hierarchy.
  • Cancel sibling co-routine (parent will cancel all it's children recursively).
  • Rethrow original exception to the parent.
• Uncaught exception on async will auto cancel siblings right away. (example)
• When you catch exceptions see if they are CancellationException if they are DON'T keep going.
• Cooperative Cancellation - coroutines must check for cancellation at suspension points, and respect it.

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Backlinks

• Kotlin Co-Routine