import java.util.Collections; | |
import java.util.List; | |
import java.util.Objects; | |
import java.util.stream.Collectors; | |
import org.checkerframework.checker.nullness.qual.Nullable; | |
public class Issue1630 { | |
static @Nullable String toString(Object o) { | |
return null; | |
} | |
@SuppressWarnings("nullness") // Issue 979 | |
public static List<String> f(List<Integer> xs) { | |
return xs != null | |
? xs.stream().map(Issue1630::toString).filter(Objects::nonNull).collect(Collectors.toList()) | |
: Collections.emptyList(); | |
} | |
} |