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Java / Java 21 Virtual Threads Interview questions

How does StructuredTaskScope manage a group of virtual threads?

StructuredTaskScope lets you fork several subtasks, each running on its own virtual thread, and treat them as one unit bound to the enclosing block's lifetime.

try (var scope = new StructuredTaskScope.ShutdownOnFailure()) {
    Subtask<String> user = scope.fork(() -> fetchUser());
    Subtask<String> order = scope.fork(() -> fetchOrder());

    scope.join();          // wait for both, or first failure
    scope.throwIfFailed(); // propagate any failure

    combine(user.get(), order.get());
}

If either subtask fails, ShutdownOnFailure cancels the other automatically, so you never end up with an orphaned virtual thread quietly running after the scope has already reported failure.

StructuredTaskScope binds forked subtasks' lifetime to:
With ShutdownOnFailure, if one subtask fails, the others are:

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