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2025-04-06 Update From: SLTechnology News&Howtos shulou NAV: SLTechnology News&Howtos > Servers >
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Option [A] is often seen in marathon source code and spark source code, so what on earth is it used for?
In fact, Option is like a container, a box; Option [A] has two results:
A, Some [A] means that the container is not empty, there is A, and then other business logic calculations can be carried out, such as calling foreach,flatMap, etc.
B and None indicate that the container is empty and A does not exist.
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