I am wondering if anyone can help me.
I have an issue with compiling some code in Eclipse but not with IntelliJ or javac.
I am using sneakyThrow to bubble a checked exception up through 2 streams.
Here is the smallest reproducible code I can make:
import java.io.IOException;
import java.util.List;
import java.util.function.Predicate;
import java.util.stream.Collectors;
public class Example {
public static void main(String[] args)
throws IOException {
List<List<Integer>> input = List.of(List.of(1, 2), List.of(2, 4));
// Should return any List whose elements are all even.
List<List<Integer>> output = input.stream()
.filter(bubblePredicate(o -> o.stream()
.allMatch(bubblePredicate(i -> {
if (i > 10) {
throw new IOException("Number too large.");
}
return i % 2 == 0;
}))))
.collect(Collectors.toList());
System.out.println(output);
}
private interface ThrowingPredicate<S, E extends Exception> {
boolean test(S s) throws E;
}
private static <S, E extends Exception> Predicate<S> bubblePredicate(ThrowingPredicate<S, E> callable)
throws E {
return s -> {
try {
return callable.test(s);
}
catch (Exception e) {
sneakyThrow(e);
return false;
}
};
}
private static <E extends Throwable> void sneakyThrow(Exception exception)
throws E {
throw (E)exception;
}
}
Compiles and runs completely fine with javac 11.0.12
, but doesn’t on Eclipse 4.21.0.I20210906-0500
nor Eclipse 4.27.0.20230309-1200
.
Has anyone encountered this before, or have any idea what I am misunderstanding?
Can you share the actual error message that you get in Eclipse?
Oh yes, sorry
The error it gives is that the inner
bubblePredicate
has anUnhandled exception type IOException
.Hm, that’s really interesting. I downloaded Eclipse (haven’t used it in years, IDEA ftw) and yes I can reproduce it. To me it looks like a compiler bug. From what I understand E should be inferred to RuntimeException, but it obviously is not. Maybe you could try to file a bug report on https://bugs.eclipse.org/