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SupplierUtil.createSupplier returns a slow supplier

See original GitHub issue

Issue

https://github.com/jgrapht/jgrapht/blob/master/jgrapht-core/src/main/java/org/jgrapht/util/SupplierUtil.java#L58

Calls getDeclaredConstructor every time.

Expected behaviour

Hoist the call to getDeclaredConstructor and close over it.

    @Nonnull
    public static <T> Supplier<T> createSupplier(Class<? extends T> edgeClass) {
        try {
            Constructor<? extends E> constructor = edgeClass.getDeclaredConstructor();
            return () -> {
                try {
                    return constructor.newInstance();
                } catch (ReflectiveOperationException e) {
                    throw new RuntimeException(e);
                }
            };
        } catch (ReflectiveOperationException | SecurityException e) {
            throw new RuntimeException(e);
        }
    }

Conclusions

LOL another performance issue from those random idiots who are doing WTF? 😄 😄

Issue Analytics

State:
Created 4 years ago
Comments:11 (4 by maintainers)

Top GitHub Comments

1reaction

d-michailcommented, Oct 1, 2019

I am mostly concerned with stuff like adjusting permissions using reflection. I can certainly try testing the resulting code w.r.t AOT before we merge anything.

0reactions

d-michailcommented, Feb 13, 2020

I tested AOT and there is no problem with this change.

Closing this one in favor of version with proper serialization (#821).

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