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?
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/