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Parallel Streams — When & Why Not

commonPool(), splittable sources, and why blocking I/O belongs elsewhere.

Pass checkpoint below

Parallel streams, honestly

Java
public class Example {
    public static void main(String[] args) {
        long count = hugeList.parallelStream()
                    .filter(this::expensiveCheck)
                    .count();
    }
}

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Test yourself

Answer these before moving on — recall is what makes it stick.